I want better ON ROAD performance too

I have a '78 CJ5 (304 V8) with Dana 44 in the rear, and Dana 30 in the front....Gearing is 4:11. It has power steering/brakes, Detroit Front/Rear and Cepek 36's all around.

ON trail it gives me everything I want. Around town (or on the way to the trail) its a bear to drive.... at about 45 mph or higher its down right tough. I dont want to trailer it and would love to use it around town more often.

Would smaller tires help? Any suggestions on size tires or other mods I could make that would get me closer to "best of both worlds"?

 

I just bought it 6 months ago and broke myself in (with a bunch of buddies) on the Rubicon. Im happy to say I am the only one that made it thru without break down... my rig was awesome. But getting there/back was a bear.

Now that spring is here again, I expect to do the Rubicon again, but most times I'd say my runs will be "beginner" to "intermediate".

I won't mind putting the bigger tires on when I go wheeling, if it would help me enjoy cruzing around town too.

I just heard (from another forum) that the issue is also related to the Detroit lockers. The recommend was to switch to ARB instead. Does this make sense?

 

The driving problem is drift... just touch the wheel and you can get squirley. Its lifted around 4" (maybe 5). Yes, the Cepek's are Radial F-C (tho Im not sure what the F-C stands for)

 

width = 15"... thx on the "F-C"... I thought it meant "Forget Comfort"

 

Haha.. hey man it's a Jeep not a corvette! Anyhow In my opinion the 36's are the biggest problem, they are so wide (especially the cepeks) that they tend to wander all over the place. The detroit of course makes corners interesting too but that is all part of owning an OFF ROAD Jeep.. The ARB's act like an open carrier when unlocked therefore getting rid of that understeer problem associated with ratcheting type lockers. They are expensive though.. The detroit is a very good unit, I would not give it up. Personally I would go to a slightly smaller tire like a 35" BFG MT and take it easy on the street.

BUBBA

 

Actually the locker in the rear will cause the jeep to get squirly under hard accelleration and deceleration. This is because of the way they operate. One shaft will spin about 1/4 turn before the locker engages this is what causes the rear end to get squirly. On deceleration it is what causes the jeep to try to change lanes.

Go easier on the throttle and it is less pronounced. Also you said you have a detroit in front. I have a locker in front as well. I have found that if I keep my front hubs locked in when I drive around the CJ is much more stable. Of course this means the front axles and drive shaft are spinning all the time. But with the little amount of on-road driving I do, I dont see it as a problem. I have driven it this way at highway speeds with good results.

 

the Detroit unit can be very sensitive to throttle response, read acceleration and de-acceleration; can move you around so to speak.
with that much tire and power steering, I'd also be looking for front suspension problems, like cracks in the frame, worn spring bushings and as Mike metioned above, TREs and ball joints.
I think a switch to a narrower tire would make a noticable improvement IMO

 

What kind of suspension do you have. I'd make sure that there is nothing broken or cracked. Make sure there is no play in the steering and suspension etc.... How much caster do you have? If your using "lift" shackles you probably have lost a little caster. Try to get it around 4* or so and see how it drives.

I'd also recommend going with a narrower tire, no wider than 12.5. Wider tires make steering much more difficult and they follow ruts in the road more. Obvously smaller tires will do better on road than big tires.

My heepo with SOA on 2.5" springs and 36" swampers doesn't feel squirely at all at highway speeds(60+). In fact I'd be very comfortable taking it to 90 if the tires weren't unbalanced, out of round swampers.

Good luck,
Kevo