MReese Wagoneer wrote:So as I await my engine from the builder I wonder how this thing is going to do with the factory 2.72 gearing.
I plan on pulling a small RV trailer , I’m used to if I have a trailer hitch hooking a trailer up and doing what I need to do, with in reason . I know it’s not a 3/4 ton pick up.
What can I expect and if I do a 2” lift and little bit taller tire.
Should I plan on a re gear.
I was happy with 3.31 gears in my J10 with 31x10.50/15 tires. I had a 360V8 with the 727 transmission, probably a lot like what you have. It towed a CJ on a trailer across flat country (Oklahoma to Iowa) with no problems. 3.54 gears would have been pretty good too.
MReese Wagoneer wrote:And would a 700R4 or 4L60 be consideration , aren’t they basically the same?
For the most part, yes. The 700R4 came out in the early 1980's. It evolved a little over the years with some upgrades. Towards the late 80's, GM switched over the name to 4L60 but it was still basically the same transmission. In the mid 1990's, GM made a big change and switched over from hydraulic control to electronic and added an E to the end of the name, so it's the 4L60E. Most of the parts are the same but all of the springs and valves were replaced with electric solenoids. This version needs a computer to control it.
I have a 700R4 in my J10 now and it was not a trivial swap. There's quite a bit of customization you need to do to bolt it to an AMC engine, and then to figure out what transfer case you'll want to run. I used adapters from
www.novak-adapt.com to bolt it to an AMC 401 and keep my Jeep NP208 transfer case. It works alright. Because of issues with the engine, I'm going to be doing a full replacement in the next couple of years and going straight to a Chevy engine with a different transmission (4L80E, stronger than the 4L60E).
And yes, if you do swap in an overdrive transmission, you will most certainly want to regear the axles. 3.73 to 4.10 is where you want to be with stock tires up to about 31". I'm running 315/75R16 tires (35") and 4.56 gears with my 700R4 and it cruises on the highway at around 2500 RPM, which is exactly where it needs to be.