Transmission opinions

[stan98tj]

This summer I plan on swapping out the 2.5l with a 1.9l VW TDI. I'll be headed out to sea soon and I wanna start getting stuff ready so I can get this going soon as I get home. I spoke with HPA Motorsports about the swap and got a ton of info from them, BUT I do have a few lingering questions. I currently run a 3spd auto and I'd like to keep the jeep as an auto (feels easier to wheel with an auto) but I want to make sure the 3spd auto can handle the new power boost. Basically this engine will be making 255 ft lbs torque at 2300 RPM, will this basically eat up my transmission and spit it out all over the road, or will my 3 spd handle it??

ALSO, gearing is an issue as well. I just regeared to 4.56 and at around 60mph i sit at about 2900 RPM, 65 has me around 3k or 3100. HPA's test vehicle is a YJ on 33s, 5spd with 4.10 gears and they are right around 2200RPM at about 65. The HPA tech advised me 2300-2900 is where I would want to be for optimal performance. Do you guys think my current 4.56 gears will work or will I perhaps need to go down to 4.10?

My 3spd auto is for a 2.5l, which I THINK may be different than the one for the 6cyl.

[saharacon87]

If you went to a 4 speed auto out of a 6 cylinder your rpms would be lower on the highway and you would have a better transmission that could handle the power. Plus then you wouldn't be throwing away the 500 you spend on 4;56s

[stan98tj]

Assuming I can get a 4spd auto for under the cost of new gears and gearing.

[saharacon87]

Yes but you would be upgrading your transmission as well. Also assuming your 3 speed auto is only for 4 bangers

[Tat2dfreak]

Your going need a stand along computer if you go to a four speed with that swap. The 42rle trans is not the strongest thing out there but could probably be upgraded with better parts. The other option would be to use something like a 700r4 from a chevy. Keep in mind you will need new drive shafts and a few other things to make the swap.

[stan98tj]

Your going need a stand along computer if you go to a four speed with that
swap. The 42rle trans is not the
strongest thing out there but could
probably be upgraded with better
parts. The other option would be to
use something like a 700r4 from a
chevy. Keep in mind you will need
new drive shafts and a few other
things to make the swap.
The adapters they make are for jeep transmissions, don't know if I could run a Chevy tranny