Strength of a 4R70W transmission?

[harry1587]

I have a 2003 GT Mustang. I am wanting to supercharge it but I am concerned that the transmission will not be strongh enough to handle the power. Are there any people with superchargers with automatics that can tell me how well they work together? THANKS

 

[billfisher]

not strong enough for long term 5.4 3v use. hard on converters.

 

[Scott_95GT]

I'm not an expert on that trans, but I hear they are VERY strong. MUCH stronger than my aode. There is a guy on here who has a 4R70W in his car which runs high 10's. Now I'm sure his 4R70W isn't stock, but still.

The 4R70w is a tranny a lot of aod/aode guys choose when upgrading. I would feel very safe with it ruinning a superchargered motor. Just make sure you get a good tranny cooler and you should be fine.

 

[MEandmyKB]

I have a 2003 GT Mustang. I am wanting to supercharge it but I am concerned that the transmission will not be strongh enough to handle the power. Are there any people with superchargers with automatics that can tell me how well they work together? THANKS

Mine is still working great and all I've added was a Ford Racing cooler. And KB's awesome shift program probably helps out some too.

 

[Stangdriver1119]

Yeah get yourself a tranny cooler and thats it, the stock transmission is definitely able to hold the power of a supercharger, pending of course we're not talking u running 20psi on that s/c cuz then you'll have other problems

 

[02LaserRed2V]

Mine's starting to get a bit sloppy. 2nd gear is hanging too much. Then again, I have no tranny cooler nor have I ever flushed it.

 

[triggz]

I think in factory spec, they're rated at like 500-600lb-ft of torque? You wont break one if you treat it right (cooler/jmod/clean fluid).

Theyre much stronger than the 5spd trannys.

 

[03ghoststang]

they are good trannies but the one that Jimmy Fitz is running is a built tranny

 

[DBMSTNG]

with my current tune i should be in the 410-430rwhp range. my tranny and torque convertor are 100% stock with the exception of a $60 trans cooler. it's holding up just fine.

 

[tomustang]

i use to beat the hell out of my 4R70W, it was the strongest thing i've ever owned, i had a cooler on it for 2 out of the 5 years

 

[timeless2]

With a cooler and proper maintenance, this transmission can handle a lot of hard work thrown at it. It's one of Ford's better autos.

 

[jimfitzgerald]

My stock tranny lasted one year when I was making 560 rwhp. Then I went with a PA Super Comp 4R70W and it seems to be holding up well for two years now.

 

[billfisher]

i stand corrected.

 

[bdcardinal]

definately put the largest tranny cooler on there that you can find. run a good synthetic Mercon V like Amsoil or Mobil 1 ATF(recently rated as a Mercon V fluid). also consider doing the J-mod. another thing to do is when you have the pan off is get the e-150 pan that has the drain plug in it, replace the screen filter in the pan and also put a filter in line, something like one of the kits from summit racing that uses a FL-1A spin on filter.

 

[gargol139]

As long as you don't make more than 420hp you should be good.

 

[Gearbanger 101]

not strong enough for long term 5.4 3v use. hard on converters.

You love plugging your car every chance you get, huh?


....and to the poster. Properly built, a 4R70W is far tougher than either the T-45 or 3650 option than the GT's got, so just sink a few bucks into it and never look back. I've seen several J-modded 4R70W's with stall converters take oodles of horsepower over several passes and never as much as a hiccup. Just don’t try to cut corners and you’ll be fine.

As long as you don't make more than 420hp you should be good.

Where in the blue hell did you get that figure from? I don't even know if that one qualifies as an educated guess?

 

[tomustang]

You love plugging your car every chance you get, huh?

his CT should be "3V poster child"

:Word:

 

[big T]

I have a 2003 GT Mustang. I am wanting to supercharge it but I am concerned that the transmission will not be strongh enough to handle the power. Are there any people with superchargers with automatics that can tell me how well they work together? THANKS

Well, I dont have any experience with boost, but my tranny seems pretty stout with what little power I have. I have a couple of friends with an 01 crown vic and 00 gt (4r70w's), both of which are use as police cars and both have 160K+ miles on them. Both have 4:10 gears and 3k stall converters (P.I.) thats been in their cars for many years and neither have tranny problems. Ive heard that these are stout trans and even stock can take a good deal of abuse...just get that trans cooler and flush it as needed (flush mines every 20k miles) and u should be good.

 

[Don 95Vert]

Mine is basically the same as your tranny - warmed over a little, but with off the shelf parts and the J-Mod. You DO need a different converter after about 350 rear wheel torque, for two reason, the stock converter will balloon and hurt the tranny front pump and/or engine thrust bearings and the single disk converter clutch will slip badly and generate heat which will destroy the tranny. Mine has been on the car 2-3 years - and my numbers are on a Mustang dyno - on a Dynojet I'd be making about 640 - and next season when the T88 goes on I should be at or above 700 - so I guess I'll find out the limits of the trannies power limits... or not!! LOL!

Don

 

[back_in_black]

I put a tranny cooler on mine and the chip tweaking of shift points and line pressure. I will be doing the j-mod in the near future. I read somewhere that the 4r70w is a lot tougher than the new auto ford is putting in the 05-06 mustangs