Home Forums Gear Hunting Trucks and Four-Wheel Drives Jeep Tranny

I'm building my dream jeep, at least in my mind. What would be the best manual transmission to put behind a SB Chevy? A "grandma" low like the old SM465 would be desireable, an overdrive high gear is a must. Does such a critter exist?

NV4500

There are a couple options. The NV4500 is the easiest period. You can try and find a ZF6 from a Chevy but those are really really rare and really pricey too. Depending on the power you are going to put through it and how you use the truck, a NV3550 may work. I think Advanced Adapters sells a rebuilt modified version. Either them or Novak Conversions.

You are building your dream jeep ? I've known people who have done that for over 50 yrs.
If you are well equiped with tools, etc, and know how, rebuilding a classic can be very rewarding.
If it's better performance over factory unit you seek, you'll need lots of money. And the knowledge to do it right. I've known very few who've actually made it happen. E

I have a 87 4 Runner to refurbish first. If I sell it I've considered finding a YJ, dropping a throttle-body SB chevy into it. I'm a passable wrench-turner as long as the wiring is simple. I think you might be able to pull it off for 10K.

Is it a CJ-5?

I had mine converted to a 350 Chevy with the Turbo 350 automatic. Dana 300 transfer case is geared really low.

Automatics rule off-road.




MSD fuel injection, dual batteries....

How long is your rear driveshaft?

Yeah, really. I had a CJ-5, the 304 was shot and I found a 305 Chevy, bought a Turbo 350 transfer adapter from Advance Adapters. My buddy and I got everything mocked up and we realized that rear drive shaft was gonna be STEEP. He said the only way it would work was to tilt the rearend up directly inline with the shaft and he said the pinion bearings wouldn't live long 'cause they wouldn't get enough gear oil. I sold the adapter to another friend who had a Scrambler, it didn't matter for that thing since it was so much longer.

Engine is mounted as far forward as possible. Aluminum radiator with electric fans; no fan on the harmonic balancer.





CV joint behind tranny





Rear Dana 44 is shimmed 4 degrees I believe

I think for a CJ-5, the only automatic that's doable is the Turbo 350

Looks like you did it right RC. NICE Jeep!

It's a tank.

Thanks!

I was gonna say, to make that work you're gonna need a CV. Doh! Nicely done.

Talked to my mechanic today about the pinion bearings not getting lube. He says you have to purposely overfill the axle.

If you are building an old JC 5, 7, or 8 I used to mess around with them some and as I remember they had a model with chevy iron duke 4 cyl that was chevy bolt patern. And had decent tranny. The ultimate set up was the Borg Warner t18 with the granny low. They came in CJs with 258 6 cyl That's what I found for my j 10 honcho.

I once watched an automatic roll backwards at a high rate of speed due to stalling out & wet brakes...

I'd consider this route http://shop.rp4wd.com/product/red-transmission along with a Warn (Saturn) overdrive http://www.advanceadapters.com/prod...rn-overdrive-for-dana-18-transfer-cases/ I'd also think seriously about going With a Chevy V6 versus the 8...

If you do indeed get a YJ get one with a 4.0 and the tranny will be fine. The AX15 is the tranny in the six banger YJs and it is also the tranny Chrysler put in the dodge dakotas with V8s. I have a 95 YJ with almost 200.000 miles. Don't run gl5 75 90 diff oil in it like the owners manual says, its a missprint. GL5 diff oil has sulfur and it corrodes the brass syncros and it shifts like crap. Mopar part number for the fill is a 10w30 motor oil. I run strait 30 rotella that is also for tranny use and gearboxes. It is a strong tranny and if you find a YJ that's one less part to have to buy. Good luck and hope you have more patience than me.