No, your fine doing a test run with front shaft only. Many folks have broken and limped home in front wheel drive. I wouldn't make it a normal or prolonged occurrence, but to do some testing or limp home you'll be fine.

 

Awesome, I'll give it a go. Just to be sure I have just removed my front shaft and will see what happens tomorrow, I'll give it a good run up to 3000 rpm. If I still have vibes I'll check with the rear off and the front in. I just checked my front pinion angle and it is currently sitting at 0* and the angle of my drive shaft is 8*, I'm thinking this is way to much angle to run the front shaft up to 2000 rpm? Don't know. I might take about 3-4* out of the caster just to be sure I don't ruin anything.

 

So I drove the jeep again with the front shaft removed and the vibration has reduced by about half, I guess this means the front is definitely contributing. All I can do for that is sacrifice some castor for better opinion angle. As for the remaining vibration I have no idea. To me it would be pointless removing the rear shaft and running it in 4hi with only the front shaft as I'm pretty certain I'll still be able to feel a light vibration from that unless I set the castor at 0*. Maybe I'll give it a shot and see what happens.

 

I'm about to have a regear done and still can't decide what to get 4.88 or 5.13. I have a 07 jku 6 speed. Heavy bumpers and all. Running 33" but will probably go 35". My biggest issue is i pull a SxS a lot during hunting season, and some to go to off road park in Tenn. In the summer. Trailer and SxS and gear probably getting too 2500- 3k pounds What yall think?

 

Running 37" on 5.13 Yukon Gears. The power is back and I can run 70mph on Texas Hwy's just at 2,700 rpm's with an automatic. No more hunting transmission going from 5 to 4 to 3 etc.

 

I'm running 5.13 on a 6 speed 3.8l with 37's. It's the right gear for me. Your RPM's with 35's are going to be above 3k at 70 so maybe 4.88 would be better. Depends on how you use your jeep. For more power and offroad/towing use you'll probably like the 5.13. For better fuel economy and highway driving the 4.88. If you are looking for something that works better with 33-35's I would say the 4.88 is better. If you are driving through mountains 5.13

 

I have 4.88 in my jeep with 35" tires and I live in san diego. Drive through the mountains alot going to the desert and big bear and it works good. At 70 MPh my rpms are just about 2900. I can cruise all the way out to the desert in 5th gear no problem. My jeep is a 2008 4 door 6 speed 3.8.

 

Thank you all,, I'm going with 4.88. i pull my sxs alot, and i do drive on the highway a lot. My hunt club is 2 hours away south which isn't hilly. I live in upstate SC. I only go to the mounatians pulling my SxS about 2-3 times a year. We do go up there hiking and fly fishing but i'm not towing anything. I'm never planning to go to 37" either. Dang tires cost to much lol. So i think the 4.88 would work out best for me. I mainly just want the regear to tow better. I hate dropping to 3rd to carry my speed while towing up hills.