I would like to upgrade my transmission from the 3L80 to the 4L80E. I have a 6.5L TD in there already. I was wondering if anybody had any info they could give so I can get an idea of what I would need or extra parts I would have to get. Will it fit with the old transfer case or do you have to upgrade. I am trying to do one thing at a time as I get the money.
If you are not looking for 'correct' parts, the civilian setup for the NA in 94/95 (and some later years) would work just fine. You need a TCM (computer) to do the shifting. Aftermarket ones are expensive, but stock GM ones can be gotten cheap if you search. A harness, some sensors (TPS, temp, baro, etc.) and a few splices are all that's needed. All TCMs (including the military) use 12volts, so you will need to provide that. Current is not much, so a simple voltage regulator would work OK...
You'd probably have to upgrade the transfer case, and drive shafts at the same time.
I'd suggest watching eBay for a takeout from someone with an H1 who's upgrading to a duramax. Oh, and as well, if you are not on the HML, do join, there's a great deal of support there, with guys who have done everything you can imagine to these trucks.
I take it your turbo is fully mechanical, right?
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My name is Peter (AKA NEHOG), and I'm never going to grow up.
(And I can't read *p o s t s* easily because of the lack of contrast between the letters and the background!)
Pm me tommorrow night, I have recently bought some humvee trans kits for the 4l80e ( lets trade) so with that said I dont know about the case will it work? also the programming? you'll have to research that but summit has controlers for the tranny or pm westech he is doing somthing with a 6.2 and 4l80 at the moment.
The engine swap was the hardest part the rest would be easy. NOS 4l80e trannsmissions are $1500, NOS 242 T-Case $300, NOS drive shafts $300, NOS military TCM in case $400. NOS transmission bracket $60, possibly having to move the emergency brake and new fuel tank (NOS fuel tanks are $50).
Other parts you will need are flywheel cover, trannsmission wiring harness to the TCM but most things can be had without to much trouble.
you can get a manual valve body for the 4l80e that would save you having to mess with a computer . the transfer case will work with the 4l80e no problem there .they put the in the civvy h1 so i'm sure you could find a cross member preety easy. the driveshafts will need to be cut or retubed but any driveshaft shop can handle that for you .you will need to mod the cooling lines ,get a filler tube for the 4l80e as they are diiferent to. and other than that the rest is minor things
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97 ram 1500 4x4
ih2410b with 130hp mercedes turbo deisel
I don't know much about transmissions so sorry if this sounds stupid. If I put a manual valve body on, then it is a mechanical transmission correct? Would it shift smooth, or would you have to add different parts on top of the valve body?
A manual body would allow (force) you to do all the gear shifts yourself, but no other changes woudl be needed. There's a but in all of this, in that the few that I know who have tried them are unhappy, as they (the shift pattern) are backwards to what is expected, and are somewhat difficult to shift.
I'd recommend the military shift system/computer. It is reliable, and proven. Actually it is basically the same computer found in the 94/95 Hummer H1s and it works well there, I've gone over a 100K miles on my 95 with minimal problems (the TPS sensors wear out at 20K intervals...)
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My name is Peter (AKA NEHOG), and I'm never going to grow up.
(And I can't read *p o s t s* easily because of the lack of contrast between the letters and the background!)
has anybody here tried replacing their transfer case with the new aftermarket selectable 2WD/AWD/4WD transfer case in their 6.2/NA? here is what it says about it and you dont need to replace any other parts.
"Now you are able to improve fuel economy up to 31% by simply installing our Selectable 2wd/AWD/4wd Transfer Case! Simply remove your stock All Wheel Drive Transfer Case and install the Predator Transfer Case for a direct replacement and an instant fuel economy savings. On average we documented a 31% increase in fuel economy. So with the average 6.5td Hummer getting 13mpg, you should now be getting apx 17mpg! The shifter acts exactly the same way it did before except that you now have a 5th gear selection, all the way forward on your gear selector, which is the 2wd setting. No draw backs or compromises at all! By selecting the 2wd setting, you are now disengaging power going to the front drive shaft and gearing thereby reducing wear and friction wich results in an increase in fuel efeciency and performance. Available for all model H1's and HMMWV's."
Transmission Upgrade Questions
