Is there a way to prevent spring sag on new springs?

[nosajwp]

I'm thinking of getting either new OEM heavy-duty springs, or new OEM UP-Country springs. I don't want them to sag, so is there anything I can do to help prevent this? Extended bumpstops perhaps?

 

[Yucca-Man]

Don't put anything in back. Because of the design (relatively flat with little arch) the springs will flatten out. There's not much you can do other than to make sure you don't overload them. Bumpstops will prevent their fully flexing upward though I suppose.

 

[fordtech]

jack it up and set the body on jackstands every night......

 

[Eagle]

I don't know what people do to kill their springs. I know a LOT of people say their stock springs are junk, but my '88 is now at about 247,000 miles and still has the stock springs. It has been driven from CT to New Mexico, SEVERELY overloaded (riding on the bump stops all the way), it has towed a small-ish utility trailer many times, it has been driven off-road at Paragon, Mohawk Trail area of MA, and various other venues, and not particularly babied.

I just measured it the other day. The rear is at 16-1/2" -- WITH my full load of minor hand tools, extra fluids, fire extinguisher, first aid kit, emergency blanket and jacket, etc. I don't think that's too bad at all.

I am now running tall bump stops, but only because the originals disappeared in a cloud of rust a couple or three years back. Perhaps the major factor is that back at around the 75,000 mile mark I dumpred the factory shocks. I ran Rancho 5000s for awhile (didn't like them), then KYBs for awhile (worse), then changed to Monroe Gas Magnum Plus (now called Gas-Matic). Those are excellent shocks and I think they prevented a lot of spring abuse.

The other thing is that I have a 5-speed and I don't make drag race starts, so my springs aren't constantly getting torqued out of shape.

 

[RichP]

I just went out and measured my 98's, 18" front and 17" rear with half tank and an LT235/75 BFG AT/KO, two full tower computers, tomken rear bumper. It's a 98 with around 260,000mi on it... shocks are whatever gas shocks sears had on sale w/lifetime warranty..... this is my third set put on last year...

 

[nosajwp]

Eagle,

Would OEM replacement Sensa-Tracs work with Up-Country springs, or would I need to get longer ones?

 

[Eagle]

Eagle,

Would OEM replacement Sensa-Tracs work with Up-Country springs, or would I need to get longer ones?

In general, Monroe (and Rancho ... same company) say the stock length shocks are good up to 3" of lift. I have a concern applying that to the Sensatracs, however, because of the "groove tube" technology. The shocks are designed so at static ride height the piston is at or near the center of the grooved portion of the shock. I don't know how long the grroves are, but my concern is that raising the vehicle an inch will bring the piston an inch higher in the shock, so you'll have an extra inch of soft down-travel before the shocks firm up.

That may not be a bad thing, but I don't know. I will be finding out, because my (very) old Monroe Gas Magnums finally became too stiff for comfort, and Advance Auto replaced them with Sensatracs. This would not have been my choice, but that's what they gave me so I'll find out how they work. And I will be putting an Up Country suspension on the '88 when I install the new shocks.

If I were buying the shocks today, I'd get the Reflex if I had the money, or the Gas-Matic if I had a limited budget.

 

[nosajwp]

Eagle,

Can you post a review of the Sensatracs once you try them out some?

Also, can you explain some of the advantages/disadvantages of staying stock height (or upgrading to Up-Country) and stock tires (or +1") vs. going with a larger lift and tires?

I'm no rock crawler, but do enjoy some weekend trail running.

 

[Eagle]

By the time I get around to installing the new shocks and new springs, I will have long forgotten this thread, I'm afraid. T'ain't gonna happen tomorrow ... or the next day. There are higher priority projects in line ahead of that. The Jeep is mobile on a used set of Ranchos, so I can wait until other projects are finished so I will have time to do the suspension right.

About the only advantage I can think of for staying at stock height (if you're going to be replacing springs anyway) is that it's easier for women in skirts to get in and out of the vehicle. However, I and many others have proven that a Cherokee at stock height is a very capable trail machine, so while I think the Up Country suspension with the extra inch of height is better, I don't think everyone with a stock height XJ needs to rush out and buy an Up Country suspension. You can run 30x9.50R15 tires at stock height, and even at one inch higher 31s don't really work that well. They'll fit, but 30s are better.

 

[MaXJohnson]

one benefit of stock height is ride quality. Keep the control arm angles close to stock for a smooth ride. No combination of cushy springs and shocks can overcome the harshness associated with steep control arm angles.

 

[rockwerks]

I'm thinking of getting either new OEM heavy-duty springs, or new OEM UP-Country springs. I don't want them to sag, so is there anything I can do to help prevent this? Extended bumpstops perhaps?

Never put em on!