...4R75W swap?

[Petrograde]

Has anyone here swapped a 4R70W for a 4R75W in a 2003 Marauder?

I assume you could bolt a 4R75W straight up,.. right?

just curious.

[David Morton]

I think it's a bolt on. Might not have to change the PCM programming, but hey, electrons are cheap enough.

What has me fascinated now is the five speed automatic they're using in the 2006 HD trucks.

[SergntMac]

I think it's a bolt on. Might not have to change the PCM programming, but hey, electrons are cheap enough. I agree, the difference between the two trannys is nominal, and not worth getting into without another reason behind that. Reprogramming the EEC for the 4R75W would be no more necessary than appeasing the owner's personal comfort.

If I were to completely destroy my 4R70W, like break a chunk out of the case, or, some other "totaled" disaster, I would buy a 4R75W to replace it. However, short of this "total failure", I would stick with the 4R70W, and follow the upgrade path most of us have taken, the Art Carr/Reinhart Stage II kit.

On the first day I owned my MM back in June of '03, I tore my rear end apart really bad...Ugly bad. The car never made it home for its first night in my garage. I came to rebuild all of it, and with all of the high quality/high performance parts available us Marauder owners at that time, which wasn't much.

Later on, in Sep. of '03, I blew my 4R70W tranny on my trip to Texas, and MV-I, and this tranny was rebuilt by Jerry W. in Detroit, while he was still a Ford Engineer, and specialist on the 4R70W. That was Oct. '03, and the parts Jerry used in my rebuild came to be the Art Carr/Reinhart Stage II kit, thanks to Dennis.

Since way back then, I've made a lot of other changes to my MM, and I've pounded on all of that very hard, no mercy. I've loaned the car out to third parties who used and abused it for more than a week at a time. The car drove the '04 Hot Rod Power Tour when I could not drive it, and it's been passed hand to hand for testing and try-outs like you would never believe.

Today, this MM is now over 500 RWHP, and running consistent 12.2x/113 MPH on Pirelli street tires, with a street tune and street gas. I've been faster, and quicker, but I'm not promoting that again, too much crap.

This beating, and this prformance, has been enough punishment to over tax my rear end rebuild of June '03, which is getting overhauled as I type this. But, it has not been enough punishment to cause a second tranny failure, not even close. Just keep watch on your tranny fluid with correct fill and color/odor, and you'll be fine. In fact, this tranny feels to be getting better with age, even as I pound on it today. Okay, enough story...

My conclusion is that the 4R70W tranny is quite capable of severe duty. It needs some modification/improvement to OEM internals and OEM EEC settings before it can prove that, but it is very durable after these issues are addressed. The 4R75W is likewise weak, and likewise strong, with the same modifications.

Should I have to install a 4R75W tranny in my MM, it won't get up in there without a Stage II kit from Dennis, and some review of my EEC.

Either tranny comes out to be stronger than we need it to be, at this time in history. When we get to 700+ RWHP, that may be another story...Just my .02C, carry on Gents.

[FordNut]

I agree, the difference between the two trannys is nominal, and not worth getting into without another reason behind that. Reprogramming the EEC for the 4R75W would be no more necessary than appeasing the owner's personal comfort.

If I were to completely destroy my 4R70W, like break a chunk out of the case, or, some other "totaled" disaster, I would buy a 4R75W to replace it. However, short of this "total failure", I would stick with the 4R70W, and follow the upgrade path most of us have taken, the Art Carr/Reinhart Stage II kit.

On the first day I owned my MM back in June of '03, I tore my rear end apart really bad...Ugly bad. The car never made it home for its first night in my garage. I came to rebuild all of it, and with all of the high quality/high performance parts available us Marauder owners at that time, which wasn't much.

Later on, in Sep. of '03, I blew my 4R70W tranny on my trip to Texas, and MV-I, and this tranny was rebuilt by Jerry W. in Detroit, while he was still a Ford Engineer, and specialist on the 4R70W. That was Oct. '03, and the parts Jerry used in my rebuild came to be the Art Carr/Reinhart Stage II kit, thanks to Dennis.

Since way back then, I've made a lot of other changes to my MM, and I've pounded on all of that very hard, no mercy. I've loaned the car out to third parties who used and abused it for more than a week at a time. The car drove the '04 Hot Rod Power Tour when I could not drive it, and it's been passed hand to hand for testing and try-outs like you would never believe.

Today, this MM is now over 500 RWHP, and running consistent 12.2x/113 MPH on Pirelli street tires, with a street tune and street gas. I've been faster, and quicker, but I'm not promoting that again, too much crap.

This beating, and this prformance, has been enough punishment to over tax my rear end rebuild of June '03, which is getting overhauled as I type this. But, it has not been enough punishment to cause a second tranny failure, not even close. Just keep watch on your tranny fluid with correct fill and color/odor, and you'll be fine. In fact, this tranny feels to be getting better with age, even as I pound on it today. Okay, enough story...

My conclusion is that the 4R70W tranny is quite capable of severe duty. It needs some modification/improvement to OEM internals and OEM EEC settings before it can prove that, but it is very durable after these issues are addressed. The 4R75W is likewise weak, and likewise strong, with the same modifications.

Should I have to install a 4R75W tranny in my MM, it won't get up in there without a Stage II kit from Dennis, and some review of my EEC.

Either tranny comes out to be stronger than we need it to be, at this time in history. When we get to 700+ RWHP, that may be another story...Just my .02C, carry on Gents.

I concur, the upgrade from 4R70W to 4R75W isn't worth the trouble/expense. A good buildup on either one is adequate.

However, my tranny experience has not been as positive as yours, Mac. I put the DR/Art Carr kit with hardened stub shaft and spiralock ring in about 50,000 miles ago. It gave up the ghost last Monday, lost 3rd and 4th gears. Granted it had numerous hard 1/4 mile passes on it while n/a with 300 rwhp, then probably 30-40 passes after the blower install at over 450 rwhp.

Diagnosis: spiralock ring destroyed, splines about to strip from direct drive drum, notches in large drum from plate tabs, a couple of slightly burned plates in each of the clutches.

This rebuild: going with Lentech race kit with 26 spline billet stub shaft and hardened mating yoke in direct drive drum (a patented mod not available elsewhere), improved production version large drum (can't recall which gears this drum is for), improved retaining ring, kevlar matrix bands & clutches, additional mods to valve body and accumulator valves. This kit is supposed to be good for 800 hp.

As for the rear end, the only problems I've had is burning up the clutches and making one-wheel-peels. If the tranny holds up and I get a good tune I expect the rear end to become a problem soon. Then I'll go with the 31 spline axles and electric locker.


edit: Don't anybody take this wrong, the previous build was done correctly, I watched it being done. It was plenty strong and lasted 50k with lots of my abuse. I did not manually turn off od, simply stomped it when I wanted to. It was a test and in my opinion the tranny held up remarkably well. And the Lentech stuff is about twice as expensive as the DR/Art Carr stuff.

[SergntMac]

50K on a Stage II kit? You did quite well, Brian, better than I expect I will. I'm about 30K on mine now and it feels good, but we all know it can go south without warning. Ditto with my rear end, in this rebuild, I moved up to the Moser 31 spline hardened axles, and the Auburn Pro diff, Ford Racing bearing kit. This ought to last me a while, eh?

[Zack]

For 100 bucks in parts off the ford parts shelf, you can bullet proof any 4R70W just as good as anyones kit. I have a better OD band, stock clutches, stock stub shaft, no rear tailshaft lube, stock # of clutches in all clutch packs. The OD return spring is beefier, top 1-2 spring removed.
The trans is trouble free besides me burning up a few od bands, which I corrected, finally.

[stryker]

Can anybody explain me what is that ART CARR/REINHEART STAGE II KIT? I ask that because my Panther is 97'and it has 4R70W transmision.


ATT.STRYKER.

[FordNut]

Can anybody explain me what is that ART CARR/REINHEART STAGE II KIT? I ask that because my Panther is 97'and it has 4R70W transmision.


ATT.STRYKER.
Art Carr makes a high performance 4R70W tranny kit with heavy duty kevlar clutches, bands, etc.

Dennis Reinhart sells that kit along with a hardened stub shaft and spiralok retaining ring to replace a high failure rate snap ring. In addition he provides a modification which provides forced lube to the tailshaft bushing and instructions to modify the valve body for higher shift pressures.

Overall, should be good to about 500 HP. Mine worked good until I put the blower on and hit 470 RWHP.