So I have been working on a 75' CJ5 that my uncle gave me for awhile now. It ran as he drove it into the shop and parked it. I have done a lot of rust killing and body work on it mainly. I painted it all and everything. I got it to a stage to put seats back in it and tuned the engine up (232 I6). I took off down the road and found that in 3rd gear(last) I would top out around 45mph with 33" tires.
I'm not sure what transmission or transfer case I have. I just kind of went to town working on this jeep. haha.
EDIT: I think I have the T-14 trans.
It is planned to be ran on the beach and around town mainly, but I need to be able to hit 55 for about 10 miles to make it to the beach.
I have a set of 35's that would probably fit, but I'm not sure how good the axles will handle them.
Can someone point me in the right direction with how to make this thing hit 55mph without blowing it up?
When I test drove my 81 CJ5, it had the same problem.. I only drove about a mile or so in a sub division. When it got up to about 45, it was pretty much there... Big tires, 258 and I wrote it off needing some work.. Got it home and let the wife drive and same results.. So starting messing with the 4 wheel drive and realized it was in low range... duh.... Anyway, shifted to hi and everything was ok on going faster than wanted to.....
It's a jeep not a mustang ha ha. I had a 75 CJ-5 with the 258 and 3 speed with 31x10.50's, it was plenty of fast enough. It would do 60-65 easy. You could swap in a 258 and put on a holley 4 barrel, offy intake, cam and header, add an HEI distributer and MSD. That will bump up the power, actually, they sell those parts fpr the 232 as well. That seems a might slow unless it has 4:88 gears are something.
1987 wrangler, 258 I-6, 5-speed.
2007 liberty sport 4X4, automatic
2009 ford ranger 4x4 FX4 OFF/ROAD, 5-speed
I'd agree with Hack. Not to belittle, but are you familiar with the shift pattern for the Dana 20? 2wd High should be just forward of neutral (in the middle) of your transfer case range. All the way forward is 4wd high. Put the transfer case lever in the middle until you find neutral (transmission in gear, engine running, and Jeep doesn't move). Then move it forward slowly until it engages. That's 2H. If you're one back from N, you could have it in 2L, which isn't an "official" setting on the D20, but you can find it on some transfer cases.
If you're sure you have it in 2H and are still getting these problems, then I'm out of suggestions. That isn't a huge engine, but you should be able to get better than 45 MPH with 33's. I would think that your stock ratio is 3.73. I've never heard of anything but 3.73's on the 72-75 CJ-5's, but I won't discount the possibility that 4.11's were offered as an option. Is there a chance that a PO messed with the gearing, either by putting higher (numerically lower) gears in it such that you're out of your power band, or lower (numerically higher) gears in it such that you're maxing out at 45mph? A tag on the diff will tell you what gears are stock (and if someone was really thinking, they may have changed it or altered it when replacing gears). If you can't find that, or don't believe it, you can jack the Jeep up, secure it, and by marking the tire and the driveshaft, you can estimate the gear ratio by counting the number of times the driveshaft turns per revolution of the tire.
locked front and rear
I also vote the possibility of being in 4 low.
By the way, the stock gearing options in that year were 3.73-1 and 4.27-1, either of which you can run down the hiway just fine, especially with 33" tires. Heck, I've got 5.38's and run down the hiway at 55-60 with no problem with 33" tires and a buick V-6
'59 CJ-5, '59 CJ-6, '68 CJ-5, Bone stock '57 CJ-5, a couple of XJ Cherokees