2005 P71 Transmission Towing Build

I'm doing the most aggressive possible transmission rebuild on my new P71. My intention is to use it to tow my other cars to the track for HPDE events. Is this the right place to document such a project? Is technical coverage of internal transmission work something that would be of value here?

I'm in the parts ordering process and the transmission is still apart. I'm hoping to be ready to assemble in a few weeks.

-Fope

What are you doing to the rear susp and axle? They're only rated for 1500 lbs because of the rear axle.

So other vehicles that use the 8.8 that are rated at 5k or more tow rating? I call on that. Even 8.8 IRS.

The uneven control arms, the very long rear overhang, those are to the detriment to towing, and putting a 2000lb cap on it is a good thing.

When a CUV with a 4 banger FWD is rated at more than twice, you know it isn't one mechanical thing.

My Escape with 180hp is so much more comfortable towing than a Panther.

I would love to see disassembly, assembly, updates, etc thread. Bulletproofing a 4R seems interesting (I never blew one up with stock power and just doing dumb stuff, which amazes me).

I don't know exactly. There are billet trailing arms, upgraded bushings, tow-assist air bags that fit inside the springs, aftermarket springs, aftermarket differentials and gearsets, and probably more available.

I've souped up a bunch of cars before, always with success, but never done a towing build or anything domestic or a truck.

I suppose that my post was pretty poorly worded, my bad. I just meant that, to my knowledge, the rear end of the car and suspension setup is the bigger limitation than the engine/trans. I'm looking forward to seeing how it comes out though.

Engine/trans has little to do with it.

A 150hp truck from the '70's-'80's can handle a tow load better than this car.

You don't need a ton of powertrain strength to pull.

The limitations are the weak chassis/suspension and the brakes. These cars just plain can't handle a heavy load safely.

That said, keep as much off of the car as you can. Get yourself a nice aluminum tandem axle with a good electric brake controller for the best chance of doing this.

If I was pulling with one of these, I'd first change the rear axle gearset so I at least stand a chance of merging onto the highway safely.

Good luck on your build. Not sure if you're looking for advice but if you're just using this car for towing purposes there is no need to go aggressive on the rebuild at all. A stock rebuild will be just fine, but where you need to go aggressive is the transmission cooler.

Anyway, good luck!

I'm always looking for advice and gladly factoring all of this in. One of the aftermarket parts I got for the transmissiom is a Superior/Translab replacement spool valve that flows fluid to the trans cooler full time.

Thank you all for the replies, and I'll post more information on this build soon.

What other cars are you towing? Unless it's something like a go cart on a small trailer proving to law enforcement that a Crown vic can safely tow a weight a lot more then it was designed for is going to be more of a problem then building the car to do it. A crown vic towing a car trailer is going to be screaming for bad attention.

Right now the track cars are VW Jettas, much smaller and lighter than the P71. I had not thought about the possibility of being pulled over for towing something that looks absurd. Honestly, I've thought more about how badass I'll feel pulling into the paddock at the track this year.

I appreciate all the commentary, and I want to clarify a couple of things:

I've found all the comments about the chassis/axle limitations very interesting, and I'm looking into this quite a bit starting from a broad theoretical level.

I have not committed to towing with the car, only fixing it because it will be my daily when my current one fails catastrophically. I will be studying, and I'll be able to justify the towing if I follow through with that role for the vehicle.

The transmission needs a rebuild, I'm very hard on cars, I can afford to overbuild it, and it's a new learning experience for me that I'm having fun with.

The initial fixing up of the car I'm also doing includes repairing every loose suspension/steering component, and new pads/rotors/calipers all around. Big brake upgrades and suspension/axle modifications are not out of the question. As usual, any advice/criticism on this issue is appreciated.

I may also be pulling the engine out to re-gasket the whole thing and deal with the broken exhaust manifold fasteners. I have not yet decided if I'm going to do it as part of this project or have it be the next one.

I'd appreciate if you can link to any technical information about this.

I agree with 2007CrownVic...if you're towing anything heavier than a garden trailer filled with mulched leaves I would recommend a brake upgrade. With the Zack and Jerry DIY brakes or something like Wilwoods, (which I have on my Marauder...all I have to do is LOOK at the brake pedal and the car stops.

I think the 2005 CV with Watt's link rear, the bags in the coils, maybe 4.10 gearing would do OK. Many F-150s use 8.8s, might look close at the axles if high mileage. I and my wife road down through SW Virginia, parts of NC, Tenn too in 1982 with another couple , visited the Knoxville World's Fair, the friend whose car we were in, was pulling his heavy old style Layton Travel Trailer with his 1966 Buick station wagon, 300 cu in V8 with a 2 barrel carb, 2 speed Buick Dynaflow transmission, it worked hard on a level road. Drove it UP to Chimney Rock pulling that heavy trailer, plus we had a bunch of stuff packed. I had put a cooler on it before the trip and he only used the AC on level or down grades as I recall. Of course, he had electric brakes and an equalizer hitch. That Layton was so heavy, we used a bumper jack to pick the rear of the wagon up with the trailer hooked so we could tension the spring bars tighter, and he had Delco air shocks.

Slow & Steady. Back in about 1968, maybe 69 or '70?, Road Test Magazine did a road test comparison of several cars, the GTXD with the 440, a Impalala SS with the 427 (could have been 454?), and a Ford Galaxie with a 429 (or 460?). I know the GTX had the 440. The cars were all automatics with HD brakes, etc. They compared top speed, 1/4 mile times, and stopping from 60 or 70 mph. The thing was, all testing was with and without the same tandem axle Air Stream trailer. They used those strap on the front fender extended mirrors too. All three broke the ton on top speed, I think it was the GTX was fastest overall. In the braking, they found the cars stopped in shorter distances with the trailer which had it's own brakes and the ratio pounds to brake surface was better with the trailer. The cars were all set up with load distributing hitches and brake controllers. Wild testing.

I don't know why I posted this, just reminded me I guess.

I dunno, I never had any problems towing small cars with my Squire. This was 20+ years ago, with an old angle-iron single-axle trailer that weighed 1100 lbs empty, with no brakes. Never had to do an emergency stop, though. The brakes weren't really up to the task, but that's box brakes for ya. Positioning the load properly to manage tongue weight was the biggest factor.

Then again, I was young & dumb, God looks out for fools and drunks and I qualify on both counts.

Tow rating was 5,000 pounds in the 1988 sales literature.



Don't know what that Prowler camper weighs, but I bet it's heavier than a Jetta on a flatbed. And your brakes are a hell of a lot better.

I would sure be interested in seeing another 4r70w performance oriented build up on here Fope. I have my 03 trans apart and I’m hung up on a lot of things cause don’t know what I’m doin. Only parts I’ve got so far are the sonnax forward clutch drum and direct drum kit. Long way to go

This is some great information, I'm really appreciating it.

HDmech:

The videos I used to get acquainted with this unit are on the "Transmission Bench" YouTube channel. The video series is dry and adds up to about 8 hours, but are very thorough and friendly to beginners.



https://www.youtube.com/playlist?list=PL9lVw8TP7bh4_mIyEjmCq5fKrG-tb2Eml

I'm also installing the Sonnax high capacity forward and direct clutch drums, so I'll make sure to cover anything I run into with them. I'm still waiting for Global Tranmssion Parts to find me Raybestos Red Stage 1 friction modules that have been on backorder. They say they can get me Blue Plate Specials, but I think they are more for a race car that gets rebuilt on a regular basis. If I can't get Reds soon, that's probably what I'm going with.

Something I ran into already is that the high capacity forward clutch drum requires the sun gear shell that doesn't have the rivets that mine had, so I ordered the later bonded shell to accommodate it.

Loads of good info here, but a few chapters were not completed...

https://www.explorerforum.com/forums/threads/4r70w-transmission-rebuild-diary.128800/

Hey Fope I’m wondering if you have the correct sonnax drum. I have the 76655-01k and my trans is an 03 and yours is an 05. 76654-01k is different and I think it works with 04 and up. I know I’m a serious noob here but something seems off

The 76655-01k is the high capacity forward clutch drum, which is what I'm using. It holds a extra friction and steel in the stack and requires that rivet-less sun shell shown above to fit because it's a little taller and interferes with the rivets.

The 76654-01k is the standard capacity smart-tech drum. They both fit both of our transmissions (as long they have the smooth sun gear shell).

https://globaltransmissionparts.com/4r70...lutch-drum-kit/

Are you using the direct drum with "built-in" stub shaft? You gotta tell us how that goes...

I've seen a LOT of failures because of worn/beat-to-death direct drum splines...

Yes I am (https://www.sonnax.com/parts/4646-smart-tech-direct-clutch-drum-shaft-kit), but it will be quite a bit of time before I can report in on long term field testing...

I love the idea of getting rid of that dinky little direct drive stub shaft. When I got the trans apart and saw that, the first thing I thought:

Failure
Of
Rational
Design

Quick update:

I've been having a lot of trouble getting the Raybestos Reds frictions, and every part supplier I've been dealing with is offering the same terrible customer service I've come to know very well in the world of aftermarket/modified auto parts.

Global Transmission claims to have them in stock:

https://globaltransmissionparts.com/aod-...-red-frictions/

Oh, wait, my bad...after rereading your prior posts...sorry for the false hope and sarcastic snicker...

No harm, I at least appreciate you being curious enough to be looking.

I'm a month into this and the first thing I can tell anybody is GTM, PATC, WITT, eBay, Amazon, and others all claim to have this stuff falling off their shelves until you put money down and/or manage to actually get someone on the phone.

All told, right now I have money down on multiple orders for the same parts from multiple suppliers that I can't get a hold of, and I just need to see what happens...

why do you think you need the RED frictions?

The Factory "green" Dynax forward frictions used in 2011-2014 transmissions is far superior to any of the aftermarket "Red" frictions.

I'll first say that I now supposedly have the Reds and GPZ direct frictions on the way from 2 different companies, and I'll see what happens.I'll bullet point the complex answer to this question from 88, which I appreciate being brought to my attention:

-This is the first I've heard of greens or Dynax.

-These suppliers I've looked at all show the same options for all years of AOD/AODE/4R70, and seem to show options for all years the trans was produced.

-The normal options seem to be the tan frictions or the High Energy.

-Stage 1 is made out to be more durable and better holding than stock, without having a blue plate level race engagement.

-The GPZ seems like the only middle ground for towing that is available, and is only available for the direct clutch.

-The 2 suppliers I have talked to agreed that the tan or HE clutches would have and issue towing 5000lbs up and down a mountain (I don't know, I'm inexperienced in towing).

-Actually I remember seeing a green friction module on wittrans, but I didn't think much of it because it had no description and I was so bent on on trying to find the reds. They have strictly factual listings of parts, that are not meant for my underinformed 'consumer level'.

I wouldn't mind paying you for a 30m phone call some evening to discuss this issue and shift kits. I have a zip kit and some superior kits (a shift kit with springs and drill bits, another with a 2-3 piston, a super servo, and sure-cool valve). I don't have any aftermarket plates yet. I'm best reached at fopeano@hotmail.com if you're interested.

I’m hung up on friction materials and glad you guys are talking about it. So many choices it does get confusing. Then throw in holding clutch or slipping clutch and waffled or smooth frictions for some more variables. That was very nice of 88grandmarq to suggest the factory frictions for the forward clutch. That works for me. Would be so easy to just go to ford and order frictions and steels for everything. Expensive but easy. Looking forward to next update Fope.

I've had such a terrible experience with parts for this project. It's par for the course even with the German cars I'm used to dealing with, but this is almost worthy of a Vinwiki car story at this point. The short version is that all of the suppliers I spent my money with, and some I didn't, did a bad job. It's only starting to come together now after 6 weeks, and get ready for a stupid read...

First I order all my rebuild parts from Global Transmission, with Raybestos Red Stage 1 frictions and Kolene steels. I asked for a matching add-on for for the extra friction and steel I need for both of the Sonnax high capacity direct and forward clutch drums I ordered from them.

Then I need a torque converter. I wanted one with a low stall speed like stock for towing, which only Monster Transmission sells, and it's upgraded. I get in touch with them and they offer me 2 bolt circles for attaching to the flex plate, 10.6" and 11.375".

Measurements for flex plate bolt circles are generally listed as 10.5" or 11.5", but that turned into a problem. To make a long story short, the real world measurements are 270mm/10.62x" or 290mm/11.38x". The Monster numbers are the closest to accurate on the market, but it ironically is a metric measurement down to the mm. Every advertised measurement is wrong, just an approximation for a truly metric number.

I contacted ADTR.net about this because they list a 10.5"/11.5" flex plate (like most other dealers) and a TCI deep trans pan I wanted (and they are a forum sponsor). Someone there texted me briefly about asking for a real measurement of the bolt circle on the flex plate they list. I was asked a few questions about my build and when I asked to get back to the point of getting accurate bolt-circle measurements, I was ghosted. Because of that, I bought the same TCI pan and a different flex plate from JEGS based on a 11.4" bolt circle in the listing. When I got the flex plate, it measured 290mm (very close to 11.4"). At that point, I pulled the trigger with Monster Transmission on the 11.375" TC and it turned out to fit exactly when I got them both together. I plan to do business with ADTR in the future because of the parts they list, but I now know better than to expect help with anything as a customer.

Then comes the problem with the clutch/steel availability...

GlobalTrans contacted me quickly to tell me the Reds are on backorder and they could only do factory Tans for now. I told them I can wait a month for them to sort out how to get me Reds, which they said they appreciated and would get it worked out. Last week (5 weeks later) I asked what was going on and said that PATC and WITtrans claimed to have these frictions and maybe they could get them there. Without responding, they finally sent my parts a few days later. The Reds came in a factory Raybestos blister pack, and the Kolene steels came in separately drop-shipped sealed-but-broken bags with rust colored blotches on the friction surfaces.

As stated, I needed an extra matching friction and steel for both of the aftermarket Sonnax forward and direct clutch baskets. Global had a single friction and steel drop-shipped for from a nearby Transtar dealer, but only for the direct clutch. I had been very clear that I had bought 2 high capacity clutch drums from them and needed additionals for both of them, but I only got parts for the direct clutch. The extra direct clutch disc that showed up was a Alto disc that did not match the Raybestos discs either in appearance or feel.

I had tried to ordered another set of Reds/Kolenes with the extras from PATC in the meantime, but that was a disaster. I first contacted them on 1/25 through web chat that was ignored, then email that was ignored, then several phone calls that were never answered. Then I just placed an order anyway on 2/14 because I'm getting desperate. I emailed them the other day about my order # and surprisingly got a response. Not that they knew what the order was, just that they were delayed by the TX/LA weather there and were sorry. Apparently that excused the 3 weeks of being ignored prior to that serious problem.

At that point, I ordered a whole 2nd set of Reds and Kolenes off Amazon.com (sold by Raybestos) for a higher cost than that any of the trans suppliers listed them just to get the issue put to bed. I could email Global and ask for the extras to be complete and correct, but their communication has been terrible despite being better than all the rest. The Amazon order shipped yesterday and I'm waiting for them to show up this week to make sure I'm good with all this crap.

I really wonder how people who are 2x/3x/4x deeper into aftermarket parts needs than I am can stand it. 20 years ago, parts suppliers I spent money with cared about their customers. These days, customer service has gotten so bad that I'm thinking of just throwing my whole car hobby away...

Wow...just WOW!

Sorry to hear about all this. I can only imagine what you're feeling...I've never had such garbage treatment from any supplier. But that all was pre-Covid and, for the most part, pre-Trump/China arguments.

Keep your chin up...it's gonna get better, and you'll be able to post your videos and successes on YouTube, get 30 million views and hundreds of thousands of $$$, retire to Abu Dhabi, and race with the millionaires in the desert!

I don't know about it ending with all that retirement glory, but I'll ultimately win this battle like I do with every automotive problem I'm faced with.

A little off-topic, but we had a older whale MGM in the shop recently and I was interested to find that the front end is really terrible compared to my 05 P71. The control arms are all thin little rusty iron twigs and the front end is a equally terrible pitman arm setup. I'm so glad mine has a rack with heavy aluminum subframe and suspension components.

Welcome to what I deal with every time I build a transmission. I order parts from 3 different vendors and If I am lucky, I MIGHT get one of them to ship me the correct parts on time. Rock auto and Amazon have been decent so far, but good luck with anybody else.

So I got a call this past week from PATC and they found my order from February in a stack of papers and wanted to know if I still wanted it. Now I have the extra Kolene steels and Red frictions I've been waiting months for. In the meantime, I did hand finish the case and had the outside of it bead blasted at my local machine shop.

Updates soon. I have to finish rebuilding my friend's E39 M5 calipers and then I can get on assembling this unit.

That's some top-notch customer service right there. At least they called to ask.

I tow with my bone stock panther about once a week for work. The boats range from 1500-3000lbs. Its definitely a 60-65 mph experience and no more. Keep overdrive off or the band will fry. I probably have around 7,000 towing miles. Plenty of trips from Orange County to Santa Barbra, San Diego and even Havasu in the dead of summer 115 degrees plus. I have an aftermarket trans cooler before the stock cooler. I've never had brake fade or any troubles braking although I always keep my distance from other cars and never push it. Sometimes when Semi's pass its white knuckle driving. Most times its comfortable driving. Expect around 9-10mpg. I also have the airlift bags in the rear springs but they feel like they do more harm then good when inflated to about 15psi. They do get rid of the squat in the rear but cause an gnarly porposing action when hitting bumps on the freeway.

After 98 when the watts link was added the tow capacity dropped to 1500. That being said often porposing is caused by too little weight on the hitch. A stiffer suspension, shocks may help here though.

I've towed with the Mercury, it has Air lifts, Bilstein HDs too. I ran about 12-15 psi, plenty stiff, no porpoising at all, but I probably had 150-200 pounds on the hitch.

I've towed roughly 5k lbs with my vic, with a total weight of 9660lbs, Wouldn't recommend it as I was going between 70/80 with 3.55 gears. But with Mobil 1 synthetic trans fluid, staying in 3rd gear, air lift helper bags, an additional trans cooler I didn't have a problem. You're much better keeping it under 65mph though. Make sure the trailer is loaded properly so you don't have a ton of the weight on the hitch and you'll have no problem. I also had a scangauge 2 to monitor temps while driving.

I appreciate the recent towing feedback on this thread in the last couple weeks. I will take it all under advisement.

I'm getting set to start putting this back together soon. I'm reviewing my Transmission Bench instructional videos again, I've got all my Raybestos Reds and Kolenes in hand, and I got a suitable tool to compress the piston return springs safely.

Very cool! It's been a loooong wait, but the starting line is here! Looking forward to new posts and pics...


Most definitely yes on both questions. Especially if you can add some technical info, such as clutch clearance measurements with the high capacity drums, for example.

I can do that. Any other requests like this would only help to give me guidance.

I've been using the video lessons from Transmission Bench to study, so there's no point in re-hashing their thoroughness, but I'm planning to make some kind of video of using the Sonnax drums. For instance, the forward drum needs to have the input shaft transferred over. I remember seeing on PATC that they have upgraded input and output shafts. I could probably double my $2500 investment in this with upgrades like that.

I'm already thinking about doing No Mercy Reversi!

It makes me wish I was as much of a producer as the things I do well. I'm just hoping that the video turns out as good as the trans repair videos I did a few years ago.

I got back in the saddle and spent about 18 hours on the trans this weekend.

I got everything all mocked up and measured and have a few questions I'm hoping the veterans might see and have some input on. I have so much other new information worth sharing, it will take a few more hours to post it later on.


Question 1:
The assembled high capacity forward clutch only has .015" of clearance when I'm looking more for around 0.075". It's so tight that I can barely get the hub into all 6 of the discs by hand.

This says I can use any combination of the included 0.055" steel (not a Kolene), thinner snap ring, or machining the piston...


I measured the clearance between the bottom of the piston and the drum by crushing .062" solder, but it did not crush at all using a press tool...




I measured that this machined land could be brought down at least .060" based on depth measurments and the solder crushing clearance, but you can see the Sonnax document says I can only machine .030" off. The machined land is more than .070" above the casting...


I can use any combination of things to increase clearance. I can use the thinner .055" steel instead of a Kolene, machine the .030" off the piston, and go to a thinner snap ring. It really seems like I can just machine .060 off the bottom of the piston land for the win. What do you think?

Question 2:
The intermediate clutch is difficult to measure, but I know I already have a problem with the Kolene steels. The new Stage 1 Red frictions are the same thickness as the stock ones removed. The removed steels are .079" and the new Kolenes are .068", which indicates there will be .044" of excessive clearance.

I cant find any kind of aftermarket solutions, or an explanation of why the Kolenes are thinner than stock. Any Thoughts?

More info coming soon when I have another couple hours to post progress...

Big Cliffhanger:The direct clutch had excessive clearance and needed a 8th steel for the clearance to spec out so stay tuned!!!

Yes I am, and I now see what you mean. Between the that direct drum/stub shaft and the forward drum, they are all the stronger Sonnax parts now. It should go well in theory, and I can assure you that this transmission will be beaten hard like all the rest.

I can't wait to be towing up the mountain with this thing and reporting back.

Disclaimer: I am NOT an expert on this transmission, or on fluid dynamics, or anything similar. I have never attained a degree in 4R7xx theory! But I have rebuilt a few of them, and have seen some common failure points, and a couple points that aren't frequently discussed here...

Having said that, I would suggest sticking with Sonnax's recommendation to mill no more that .030 off. I would think that any more could impede fluid flow through the 3 channels, maybe create unwanted vortices, who knows... That is the forward clutch, after all. You want to have it apply quickly and evenly, to ensure long life...

The links below revealed something to me that I have not seen discussed much, if at all, on the forum. These are grooves in the case from the intermediate clutch steels banging into the sides of the tabs. They were causing the steels to not ride smoothly up and down, and were an obvious point of failure for this tranny. Just something anyone who is rebuilding should watch out for.

Associated post:
https://www.crownvic.net/ubbthreads/ubbt...357#Post2732357

https://i.imgur.com/yBfIkrB.jpeg
https://i.imgur.com/KNGiPeV.jpeg
https://i.imgur.com/xZ1WxCN.jpeg

And, once again, a link to my favorite 4R70W rebuild:
https://www.explorerforum.com/forums/threads/4r70w-rebuild-diary-part-13-intermediate-clutch.159423/

Hope you can find some useful info in all this...

Hold on! Just found something interesting from:
https://www.explorerforum.com/forums/threads/4r70w-rebuild-diary-forward-clutch.158888/

Quote: At the back of the clutch is a "wave plate"... see Jerry W's article for a discussion. I am using a 3 wave plate in this transmission... there is a thinner 5 wave plate, used in the 5.4 liter applications, giving you a little more room in the clutch. In fact you can do more or less like we did with the direct and sneak in an extra plate using this wave plate and omitting the top pressure plate and instead using a steel. Worth considering depending on your use. End quote.

This is all very useful and appreciated. Thank you so much!

If you read that picture of the forward clutch instructions, it mentions the wave plate being two different thicknesses and heights but doesn't describe as being 3 or 5 waves. There is something for me to investigate here, as well as the mention of replacing the top end plate with steels.

The info about the intermediate plates wearing the case is interesting too. I still haven't found any solutions to the thin Kolene problem other than ordering OE type steel plates that might not be available at the moment...

I'm really starting to wonder why all these Raybestos Kolene steels are .068" when it seems like all the stock steels (except for the reverse it seems) are thicker. I have yet to find a mention of this being a thing, but it's a big discrepancy I'm measuring when it's advertised as a 'stock' rebuild option but only matches 1 out of 4 of the steel packs it's replacing.

The Raybestos Red frictions all match the factory thicknesses. It seemed innocent to expect the Konlene steel set to also match the stock thicknesses, but they are all thinner and it's jamming up my operation like a boss.

You're quite welcome.

I see what you mean by the wave plate...all Glacier says is that the 5 wave plate is thinner...Is he referring to the overall 'height'? I don't know either...

And can't speak to the Kolene's thickness. I've never digressed from straight stock (translation: cheapest available solution!). I'd pay attention to the various thickness steels available, and maybe consider swapping the end plate with a thicker steel...

Good hunting with the research.

Quick update. Useful details coming soon.

I got the clutches clearanced well, but they all can't be perfect with all these aftermarket parts. Not quick, simple, or easy. I will post the details of the clutch pack clearances and how I achieved them.

In the last 2 weeks I've closed on my home with an included rental property, bought a 35 year old BMW 325, bought a electric bass and amp setup, booked upcoming track days, and bought my best set of track tires/wheels yet for the VR6.

The trans is so close to final assembly. I just need to fit the shaft seals properly, air check them with the associated clutches, and then I can install the case components.

The valve body/shift kit work that tops it all off is a breeze. Watch my Honda transmission videos if you want to see why I say that. This trans is going to be really great.

There is still hope that I will tow something to the track this year...