A question of stance

[Dechion]

I found recipts in my MJ when I bought it showing that the rear leaf packs had been replaced, but with very little in the way of details.

 

To me it looks like the PO might have had replace the rear with different springs. I do know that I am running 235/75-15's in place of the stock tires. Maybe this was the beginnings of a lift?

 

 

Anyhow, to me it looks like the stance is pretty far off level. Any thoughts?

[mvusse]

Comparing your photo to photos of my 87 4wd as well as my new (originally 2wd, which supposedly sits 1" lower than 4wd) 87, I notice two things:

 

1 - Rear springs seem to sit high for regular stock springs. Could be Metric Tonne leafs, or 3" lift.

2 - Front has sagged a LOT. Like 2-3".

 

I would replace your front springs with new stock ones, or even stock V8 ZJ ones or XJ Upcountry ones, both of which sit about an inch higher than stock.

[Dechion]

anyone know the stock measurements for front and rear? ground to fender flare or center of rim to fender flare?

[mvusse]

FSM specifies stock measurements and where you measure (pretty much axle to frame). The info is floating around here somewhere.

[mvusse]

Found it:

Here's a repeat of the "Official" way to measure ride height, from the MJ FSM (Factory Service Manual). Actually, not in the FSM but in a book of IS bulletins that came with it:

 

Front: Measure from top of axle tube to underside of frame rail, inboard of the coil spring. Do NOT measure from the diff housing or shift motor housing. 2WD models should be 6-3/4" plus or minus 1/2". 4WD models should be 7-3/4" plus or minus 1/2".

 

Rear: Measure the vertical distance between the top of the axle tube and the underside of the frame rail inboard of the jounce bumper. 2WD models should be 8.2" plus or minus 1/2". 4WD models should be 9.2 inchws plus or minus 1/2".

[Dechion]

thanks much, I'll have to get outside and put a measurin' stick across it and see what I have to work with.

 

My original thoughts were to lift the front to match the rear, but I need to know where I am to know where I'm going.

[ComancheKid45]

Stock from center of the wheel to the bottom of the OEM flare is 17.5" front and 19" rear.

[mvusse]

Stock from center of the wheel to the bottom of the OEM flare is 17.5" front and 19" rear.

 

Says who, and is that for 2wd or 4wd?

[Dechion]

Mine is an 89 2wd (oh how I wish it was a 4wd)

[ComancheKid45]

Says who, and is that for 2wd or 4wd?

 

 

I know for a fact the XJ measurements are 17.5" front and 17" Rear, I'm pretty certian i read at some point that MJs are 19" rear. wether it was a 2wd or 4wd measurement is beyond me.... :dunno:

[Eagle]

Says who, and is that for 2wd or 4wd?

 

 

I know for a fact the XJ measurements are 17.5" front and 17" Rear, I'm pretty certian i read at some point that MJs are 19" rear. wether it was a 2wd or 4wd measurement is beyond me.... :dunno:

17-1/2 for the front is correct (I think that's for 4WD), but 19 for the rear sounds low. Maybe that's for 2WD. I've measured a bunch of MJs informally, and my impression is that the rear should be somewhere around 21".

 

Either way, a fiberglass cap is a fair amount of weight, and visually the rear of that truck is quite a bit higher than a stock MJ without the cap. I'd guess the rear springs are the equivalent of a bout a 3" lift.

[Dechion]

Ok, for what it's worth I went out and put a tape measure across the outside (too late at night to crawl underneath) and here is what I came up with.

 

2WD MJ 16.25 front 20.5 rear

 

4WD XJ 17.5 front 17.0 rear

 

measurements are center of the rim to the bottom of the fender flare, and were taken without a square by the light of a streetlamp, so call them +/- a quarter inch or so.

[mvusse]

I just measured my stock 87 and there is ~12" difference between the axle to frame and center of rim to flare measurements.

 

So converting the FSM numbers, from the center of the rim to the bottom lip of the rear flares:

 

2wd: 20.7-21.7

4wd: 21.7-22.7

 

With Motion Offroad 3" lift rear springs (I believe Hell Creek springs are the exact same) I had 22.5", or near the upper end of stock 4wd specs.

[Dechion]

Looks like I will probably end up picking up a set of either stock V8 ZJ or XJ Upcountry ones to get a bit bloser to a level stance. That should give me about 18.5 front and 20.5 rear. I may even put in a 1" spacer to bring the front to about 19.5.

 

I should probably replace the front shocks as well if I do that though.

[mvusse]

You could also get some 1.75" spring spacers and 2" shock extensions for a less expensive option.

[Automan2164]

Looks like I will probably end up picking up a set of either stock V8 ZJ or XJ Upcountry ones to get a bit bloser to a level stance. That should give me about 18.5 front and 20.5 rear. I may even put in a 1" spacer to bring the front to about 19.5.

 

I should probably replace the front shocks as well if I do that though.

 

I have a set of Upcountry XJ coils you can have.

 

Out of a '94 with 110K.

 

Rob L.

[Dechion]

Looks like I will probably end up picking up a set of either stock V8 ZJ or XJ Upcountry ones to get a bit bloser to a level stance. That should give me about 18.5 front and 20.5 rear. I may even put in a 1" spacer to bring the front to about 19.5.

 

I should probably replace the front shocks as well if I do that though.

 

I have a set of Upcountry XJ coils you can have.

 

Out of a '94 with 110K.

 

Rob L.

 

Thanks much, I'll have to get together with you one day soon. Harvard isn't that long of a haul from Kenosha.