im researching lifts and ive come across this 5" coil spring conversion from Pro Comp for my '90 Wrangler. it says that it will make my ride a lot smoother which would be great considering that ill be more on-road than off-road most likely. ive read reviews about it and they all say pretty good things about it and that it preforms just as well as any other lift. has anyone put this on or heard anything about it? thanks

There was an article in one of the mags a couple of issues age, I thinl it was JP and they seemed to like it quite a bit.

personally,I had a bad experience ( stiff ride quality) many years ago with pro comp leaf spring suspension assembly; but recently I've either read or heard in a conversation that pro comp coils provide a comfortable ride quality. Makes sense to me that any coil suspension would be the best way to go if I was building a CJ-7 or YJ just for the highway. I suspect that leaf springs have the advantage offroad in providing better control of the axles during hill climbs and rockcrawling.

Aren't leaf sprung vehicles the ones that tend to get "axle wrap" whereas coil sprung ones don't? Or have I got it backwards....never had a problem with axles going where they ought not to on the TJ.

I think the panhard bar on coil sprung rears help prevent axle wrap. Leaf sprung rears don't need the panhard bar because the springs are mounted to 2 points on the frame...coils just 1. Not to mention the control arms on coil sprung Jeeps.

You might want to do a Google search on "Black Diamond coil conversion". Black Diamond, which is now owned by Superlift, makes the conversion kits. They're pricey, but reportedly do a good job. The front is converted to a coil suspension similar to TJ, and the rear is converted to a SOA leaf spring configuration. The Google search I did had the manufacturers layout, some distributors' words, and some test reports by various individuals.

Fred, fellows, the TJ has taken on road drive quality to a level that leaf springs can't touch. The off road quality depends on what lift kit. For example 5" lifted TJ with short arms wheeling on Moab will be out matched any day by a 4" SUA CJ7. Install longarms (like RE) on the same TJ and you have no contest, leafs are dead.

Just like with anything, some kits are better than others.
Prochump kits tend to stink for many reasons, the cheap price is what always gets them noticed.

Blackdiamond coil kits were cool 12 years ago, today they are proven to be hard to install, have to remove the entire suspension to do a clutch job (ick), bushing poppig out JUNK.

The bottom line is...drive a TJ, you won't look back, sell the YJ and buy a TJ.

SD

Ditto what SD said. For all the work/frame butchery that would go into a coil conversion on a YJ, you'd be WAY ahead to trade up to a TJ.
One more point- A panhard bar (or track bar) does nothing to eliminate axle wrap. It locates the axle side-to-side under the Jeep. A lot of guys new to Jeeping are reading this- let's be sure our answers are accurate.
Corona <img src="/forums/images/graemlins/cheers.gif" alt="" />

With great respect for you and your knowledge in these matters, Superdawg, I'll stand with my comment above simply due to observations I've made of TJ's and built TJ's traversing difficult trails. One point you made above all the others is that some kits are better than others. I guess that's where it's great to have a site like this one to run build ideas by and possibly get a real mechanic's opinion sometimes; unless you're fortunate enough to have a 4x4 guru tucked away in a neighborhood 4x4 shop that can properly guide your Jeep build!
Yes, axle wrap is a major concern with SOA setups, seems especially true for YJ's. But, axle wrap can be addressed with a simple traction bar add-on; a dependable solution, but not bombproof on extreme rockcrawling trails for a horsepower-over-obstacle mentality; the type of trail moron who never learned to finese the Jeep over the obstacles!
One of the most memorable TJ climbs I've observed in the recent times was on Hummer Rock (at least that's what it was being called on that particular trail ride) along the Poison Spider Trail, the RE Lifted TJ was climbing up on the rock face, 50 to 70 per cent slope, and the rear coils squatted! Obviously, the front tires lifted SEVERAL inches off the rock surface and the TJ was momentarily balanced on the two rear tires. It didn't roll, but it must have been a white-knuckle moment, nonetheless. No, no coils on my rockcrawler, thank you! At least for now! <img src="/forums/images/graemlins/lol.gif" alt="" />

Fred, was that TJ on Short arms or long? no contest, the long arms I've seen in action don't do that.

I'll give you that a leaf spring is predictable, but even that is tossed with revolvers or other ramp trick BS.
Those POS shackles will unload unpredictably.

SD