[burganb]

I didn't find a post completely devoted to this upgrade so I figured I'd start it off. I think I found the greatest upgrade for the 4.7L (with help from HemiDak on Dakota-durango.com), the 2002 Jeep GC TCM swap.

Personally, I Haven't been able to try it out but I have done enough reads on it to know people like this mod. If you have a 2002 and back dakota with a 45rfe tranny in it with the seperate TCM setup, here is the mod.

Take stock Dakota TCM out of truck by unplugging connector and unscrewing 2 bolts. Then take a 2002 Jeep Grand Cherokee 4.7L TCM put it in the engine bay use same two bolts and same connector. Screw in the bolts and plug the connector in. There you're done.

I've heard of 2-3 MPG gains, even on Dakotas running 4.56 gears and on 4x4s. And the part you can find relatively cheap. Found mine in a yard up in MI for $57.70 shipped to me with a 30 day warranty included. But most people have found them for about $60 shipped. I think one guy on Dak-dur found one for $45, but that cause the guy quoted him a $65 and he said he found one for $45, so the guy price matched (good luck if you want to try doing it that way)

Anyone else that has done this mod. Put in y'all feedback as well.

 

[SH0K0TA]

i know a couple ppl here have done it.

to further explain this, the 4.7 dakota and jeep engine/trans setup is the same. but if you order a trans for a jeep, its different from the dakota... but why might you ask?

the TCM for the jeep allows the trans to use the 5th gear in the dakotas. its kinda "hidden" for the dakota 4.7s.

all it does is unlock the hidden 5th gear and it'll let you RPMs be lower at cruising speeds. therefor you get the MPG gains.

you can also cut the torque management wire (i think its a solid yellow one) and that'll firm up shifts esp at WOT

 

[burganb]

Yeah that bit about ordering the tranny and it being different is right. I had a buddy order a tranny for his jeep and he had to specify that it was a 545rfe, not a 45rfe, which is what is in the dakotas. Even though its the same tranny.

 

[krazykane]

so ths upgrade is for mpg not over all hp

 

[madmopar]

if you eleiminate your speed limiter, it would also give you a higher top speed, because you wouldn't be turning as many rpm's at any given speed.

 

[burganb]

Yeah, I've got the program taking the speed limiter off and the TCM is swap. She runs great minus the fact that the cats are almost all the way clogged.

 

[edgeofvamp]

So anyone that has done this, what are you running at for rpm's at 70mph?

Cause with everything in my stock 01 dak 4x4 sport i am just hitting 2000rpm at 70 mph.

 

[bballbrownie34]

I have a 2004 Dakota QC and I am running about 1900 rpm at 70 with 4:10 gears. Im pretty sure I am using the 5th gear too, I think they opened that up in 2004.

 

[bobbyk]

3 year old tread....

 

[BigBear1972]

Yeah, I've got the program taking the speed limiter off and the TCM is swap. She runs great minus the fact that the cats are almost all the way clogged.

Can I get a copy of this program to remove the limiter off my 02 Dakota & 03 Durango?

 

[mikereiling5]

if you eleiminate your speed limiter, it would also give you a higher top speed, because you wouldn't be turning as many rpm's at any given speed.

How do I turn off speed limiter I have 05 Dakota 4+4 4.7l quad cab