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Unread 01-30-2009, 07:13 PM   #16
SeaWulf
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You could also try swapping the springs from one side to the other.

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Unread 01-30-2009, 07:31 PM   #17
Renegade79
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i remember reading a thread a while back about twisted axle tubes causing jeep lean. the tube/housing connection on the amc20 is a weak point and under enough stress one of the tubs could twist a little and cause the jeep to lean one way or the other.
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Unread 01-30-2009, 07:48 PM   #18
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I'm convinced that it is a factory defect. Too many incidents of it.

I'm in the process of restoring a CJ5 frame, right now. I finally got a good chance to measure everything for squareness, levelness, etc.

The amount that my frame is out (of square, etc.) is the same as a lot of others that have posted in other threads.

If anyone's interested, here's a link to my frame restoration, on another forum...

http://jeep-forums.4wd.com/showthread.php?t=36592

Rich.
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Unread 01-31-2009, 11:30 AM   #19
mcurcio1989
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I heard someone mention something about the way they were attached to the trains for shipment. I could be wrong and I am not sure if jeep built there frames on site or not but my jeep is toledo born and raised and it has that lean. I kinda just assumed it had something to do with the po being heavy and causing an uneven weight distribution to the springs. It would make sense that it is a manufacturers defect tho because it's way to common.
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Unread 01-31-2009, 12:07 PM   #20
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On AMC Jeeps, the factory steering stabilizer mount is clamped between the driver's side spring and perch so that would contribute to the problem but not to a great degree since the mount thickness is only about 3/16".
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Unread 01-31-2009, 12:57 PM   #21
danholovic
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During my ongoing CJ rebuild project (have been working on the frame for several months) I noticed that my frame was off vertically about 1-1/4". This measurement was taken when the frame was supported on all four spring hangers so that everything should have been level and even and everything. The front of each rail was right, but in the back, the end of one rail was about 1-1/4" higher than the other, which would certainly add lean. This frame had severe cancer, but presumably was unwrecked (you never know...).

I measured and figured every way I could, but in the end, it seemed that something in the wheel arch on one side was different from the other. I cut the frame and bent it to perfect alignment - now it's gonna sit perfectly level (I hope).
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Unread 01-31-2009, 03:38 PM   #22
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Quote:
Originally Posted by danholovic View Post
During my ongoing CJ rebuild project (have been working on the frame for several months) I noticed that my frame was off vertically about 1-1/4". This measurement was taken when the frame was supported on all four spring hangers so that everything should have been level and even and everything. The front of each rail was right, but in the back, the end of one rail was about 1-1/4" higher than the other, which would certainly add lean. This frame had severe cancer, but presumably was unwrecked (you never know...).

I measured and figured every way I could, but in the end, it seemed that something in the wheel arch on one side was different from the other. I cut the frame and bent it to perfect alignment - now it's gonna sit perfectly level (I hope).
I agree, Dan. My frame rails sit parallel everywhere, except from the wheel arch, to the rear of the frame. I actually had the right side frame rail tilted , heightwise (camber).

Where did you cut the frame to lower the higher end?

Also, when you said that your frame was resting on all four spring hangers, did all eight spring hanger tips touch the surface they were sitting on, at the same time?
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Unread 01-31-2009, 04:21 PM   #23
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I read somewhere on the NOVAK conversion site that CJ motors(the V8's at least) were offset to the driver's side a bit (cant remember why)....I would think the offcenter weight could be the cause of the lean......
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Unread 01-31-2009, 08:37 PM   #24
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I do not think I have ever seen a Spicer/Dana 18 equiped CJ that didn't have some driver's side lean. I think if you weighed each spring position you would find notably more weight on the left side due to the offset motor and transmission. Weighing just the wheels will not give you a good comparision as the diffs (unsprung weight) somewhat compensate for the motor and trany. I do not think the lean is due to a lot of frame warp (at least in most cases). I boxed my frame with 3/16 and it is very rigid. When I installed 2 1/2 Rancho springs, it rode level for about 15 years before slowly developing the lean again. Any long term solution will likely have to have left springs with a slightly higher spring rate, or just buy quality springs and plan on replacing them every 10 years.
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Unread 02-01-2009, 12:26 AM   #25
crusty75
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On the older 75 and down jeeps, I'd bet almost anything that it DOES have something to do with frame flex. Boxed frame, not so much.

The older frames were designed to flex, it sticks in my head somewhere in the neighborhood of 7", if I remember correctly.

Hence, the school of thought out there that if you are gonna box an old jeep frame, you better do it right, and do it all, or you'll get cracks. I've seen it a time or two with my own eyes. This school holds that it is better to strap the frame, maintaining flexibility.

That being said, the same problem crops up, even in jeeps with frames boxed from the factory (post 76).

Engine weight bias could certainly have something to do with spring wear rates though... from what I understand, an F Head weighs more than a straight 6. Thats why they call it "old iron" I guess.

I suspect the "why" of the phenomenon will be discussed over the campfire well after we're all dead, with no definitive resolution ever reached. This is why I like jeeps, the things are almost human in their capriciousness.
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Unread 02-01-2009, 09:54 AM   #26
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Many jeep frames are out of square (corner-to-corner), also. Mine measured 1/2" difference c.t.c. (=1/4" out of square), I come-alonged it, and added gussets to 2 of the rear crossmembers, to keep it there.

I still say that factory frames are far from perfect.

As a matter of fact, the spacing between the spring mounts were different, between the right and left sides of the frame.. I'm gonna fix that, too...

http://jeep-forums.4wd.com/showthread.php?t=36592
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There's a fine line between "hobby" and "mental illness".
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Unread 02-02-2009, 08:39 AM   #27
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ok now i am back to square one again.... pulling my hair ( all six of them ) out and wondering aloud if it is worth messing with in the first place.. but thanks for all the helpful...ahem... insight, o by the way if i could blow up avitar i would but, that picture is of my girlfriend and if my wife seen it she would be pis-ed!!!!!!!
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Unread 02-02-2009, 09:07 AM   #28
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Quote:
Originally Posted by baystrucksalvag View Post
ok now i am back to square one again.... pulling my hair ( all six of them ) out and wondering aloud if it is worth messing with in the first place.. but thanks for all the helpful...ahem... insight, o by the way if i could blow up avitar i would but, that picture is of my girlfriend and if my wife seen it she would be pis-ed!!!!!!!
If the lean is less than an inch, I personally feel it's not worth messing with. After a while you get used to it.
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Unread 02-02-2009, 12:45 PM   #29
danholovic
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Hi rixcj:

Yep, I also had that "camber change" on that side just like you mentioned. I didn't do anything to fix that, but here's what I did to the arch thing:

First, yep, all eight of the little ears touched. At the time I started all this mess, I had removed both crossmembers from the back of the frame - the rear one and the one in front of the gas tank - so all I had was the two frame rails connected by the front crossmember. This let the frame fall down into good alignment so that all the spring hangers were touching at the same time. It also turns out that both frame rails were parallel to the ground so I didn't have to do anything special to get it level.

Earlier in the process I had plated all four sides of each frame rail with 3/16" plate from the very back up to just forward of the curve where the rails make the first turn in. I then used 3/16" plate just on the inside and outside of each rail from that point all the way to the front (almost all the way to the front on the inside - I stopped under the shock mounts). My frame had severe rust damage and could have been a write-off, but I thought it would be fun to fix it - now it's as strong as an F-350.

When deciding where to make my cut, I measured carefully at many points beginning at the straight middle area and progressing all the way to the rear end of each rail (every two-three inches or so) - I measured from the floor to the top of the frame on both sides. I compared left and right sides and found that for awhile the numbers were the same. However, about eight inches up one arch, or about eight inches from where the rail changes from straight to curved, I found that the numbers began to deviate - one side was moving away from the floor faster than the other side.

At that point I made a cut all the way through the top and both sides of the higher rail (didn't cut the bottom). Gravity then pulled it down so that both ends were now the same distance from the floor. Once the bend was made, all those other measurements became almost the same from left to right, meaning that there had been a difference in the radius of the arches on each side.

Once the higher rail was bent down, all the curves matched and the ends of my frame were the same - presumably my Jeep will now sit level. I was then left with one frame rail with a quarter inch wide cut in the top, and a pie-shaped cut all the way from top to bottom on both sides. I put some round rod behind each cut to support the weld, chamfered each edge in a big way, then butt-welded all three sides.

With the 3/16" plate on all four sides that I had previously installed, plus whatever remained of the original frame also being included in the weld, I imagine this would be plenty strong enough. But just to be sure, I made 1/8" plates about 6-7" wide to go over all three repairs, plus the uncut bottom side. I thoroughly plug welded these, as well as edge-welding them. I have no doubt that the frame will break somewhere else before it breaks in this area, but I think it will have to be run over by a tank before anything happens.

To decide if the high rail need lowered or the low rail needed raised, I checked the frame measurements listed here and there (with some of the numbers corrected by Forum members) and picked which rail was the one that was off from specification - it ended up being the high rail for me (can't remember if it was left or right).

I also checked many, many times throughout the process for frame squareness and proper frame width at all locations - sometimes I had to put the Hi-Lift in there to move something before welding.

Right now, except for some cosmetic stuff, my frame is very sqare and level, and it's way stronger than it was before. Hope this helps! Holler at me if you want some pictures - I took a bunch of 'em!

Dan.
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Unread 02-02-2009, 02:03 PM   #30
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Thanks, Dan

That's a great explaination of your process. I've been deciding which rail end to change, as well.
The center, straight sections are parallel to each other.

I took a 6 foot long length of flatbar (14 ga. x 2" ), and rested it,up on edge, lengthwise, on the top of the center section, and let it reach the end of the frame rail. On one side, the short run of frame after the arch, is parallel to the center section. On the other side it isn't (it kicks up).

So, I've decided to modify that side. I think it's supposed to be parallel to the other straight elevations of the frame.

Does this make sense? Does my explaination make sense?

Rich
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There's a fine line between "hobby" and "mental illness".
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