We just acquired a 93 Wrangler, it appears to be completely stock with the 4.0L I6 and manual tranny, except for the 35" BF tires, fancy rims and lift kit... It runs great, and is in good shape. One question though... It gets right up to a cruising speed of 55mph and tops out. I assume this is likely a gearing issue? We'd like to hop on the interstate with it if needed... Any thoughts on what sort of upgrades would bump up the top speed a little bit?
Firstly, get rid of those shackles.
Your issue is most likely the gearing with those 35s. If you have a D35 in the rear than you could downgrade to 31/32s (with that shackle lift gone it would look good) and improve your fuel mileage, at the same time preserving your turdy five a bit longer.
Yeah, that rear axle won't last long with 35's, even on the road. You can trade those straight up for a brand new pair of 31' or 32's, and yes get rid of those buck tooth shackles before they too give you a massive headache.
Thanks for the info. A little new to the jeep thing. When you say remove shackles, do you mean loose the lift all together, or lift another way? And if we'd like to keep the 35's is doing an axle and gear swap the best thing to do? and if so, the 8.8 conversion the best option?
We arn't looking for the cheapest solution, but rather something that will make this thing last a while.
It will last quite a long time on 31" tires as long as you have a light foot. 35" tires is going to put way too much stress on the D35 rear, even just rolling down the road. An 8.8 swap will set you back between $300-$500 depending on where you source parts, maybe even more. Re-gearing isn't cheap either, it will cost you anywhere from $400 to $800 depending on who does it, and that's per axle. The cheaper option is to find stock axles that already have 3.55, 3.73, or 4.11 gearing in it and swap them right in. You should have 3.07 as stock.
I would list your tires up for sale on Cragislist or here, one of the local offroaders will probably go for them. Maybe even trade you straight up for a brand new pair of rubbers in a 31" variety. Removing the shackles is a good idea, you can run into issues with shackles that long (pinion angles, vibrations, etc.). A pair of 1" boomerang lift shackles can be had for around $100 a pair, and trust me, you want to do it fast. Plus the 31" tires won't rub at full spring flex, those tires are almost guaranteed to.
Also, keep in mind the speedo might not have been corrected. If it reads 55mph then you might actually be going somewhere near 70mph.