Inner Tire Wear Issue

[markfothebeast]

99 Explorer AWD
4.0L V6

After replacing the upper control arms, ball joints, inner and outer tie rods, and wheel bearings I brought it in for an alignment. I told them to adjust the adjustable upper control arms.

A few months later the front tires wore down at the inside. I do not drive it but my roomate does. I drove it and the tires howl and it pulls side to side on the highway. Simply because it is riding on the inside of the front tires. I called the alignment shop and they looked at it. They said it needed shocks. But I don't understand how the shocks can cause this. Than I thought about the torsion bars possibly needing adjustment. I would think the torsion bars would throw the camber or castor off. How can I check that the torsion bars are correctly adjusted?

 

[koda2000]

If the tires are wearing on the inside or outside you need to adjust your outer tie rods. right now your tires are like this... \ / when they should be like this... I I with a couple pf degrees of toe-in.

Shocks would have nothing to do with that type of wear. When your shocks are real bad you tend to get cupping on the front tires. I can't say whether your shocks need to be replaced, but your wear pattern sounds like bad tie rod adjustment.

 

[96eb96]

For the torsion bars, there is a height adjustment procedure in the service manual where you measure between two points. The lowest point of the control arm(around the ball joint bolt, at the bottom of the cast arm) and the LCA bushing bolt centerline. Subtract those two measurements and you come up with a number.
3.58"-4.37" is the acceptable range for a non air suspension worn in ex.

Definitely sounds like an alignment issue. Sears used to do free alignment checks, but they are getting few and far between.

 

[markfothebeast]

Went back to the alignment shop twice. They claim that the alignment is up to spec but the shocks are the problem which is BS. There is nothing more they can do. That is why I was wondering about the torsion bars. I've done many tie rods and ball joints and understand the theory.

7 years ago I had a 94' Mazda Navajo (Explorer) and I cut the springs and lowered the torsion as low as it could get. One thing I noticed when I lowered the torsion was the camber went way out of spec, understandable. Now that's what I'm thinking on this 99'. The torsion tension may have eased up over 17 years and lowered itself down causing the tires to ride on the inside because of the lowered height and the changes in geometry from new suspension components. The rear end sags like a *****. Clearly because the leafsprings are old.

 

[markfothebeast]

The passengers wheel is 6-1/8" from the lip of the fender while the drivers side is slightly under 5-3/4".

 

[SWIGIN]

The problem is toe adjustment.

Mine does it too but i'm holding off till I do my SAS and ditch all that independent crap...lol

 

[markfothebeast]

Toe was checked twice.

 

[BKennedy]

You are right, shocks don't have anything to do with this type of tire wear. They dampen the movement of the springs. Like Koda posted, if they are bad you sometimes get cupping type wear. It seems to me that with tire wear that extreme, you have negative camber, causing most of the vehicle weight to be riding on the inside few inches of the tire. Find another alignment shop.

You can check the toe angle with a tape measure. Easier with a friend. Pick a spot on the rear portion of the tires. Measure the distance between the tires. Repeat procedure with the front of the tires. Should be 1/4-1/8" less distance for front measurement.

 

[markfothebeast]

Like I mentioned, it was put on a laser alignment machine twice, apparently. According to the numbskulls at Johnson Goodyear tire in Red Wing, MN. I can use my godamn eyeballs and see the inner angle while it sits in the driveway and they tell me the shocks are worn. The shocks are as solid as a rock.

 

[markfothebeast]

I tried to upload photos but it needs a host. Anyhow, under the vehicle it is very clear that it is has such a ridiculous negative camber.

 

[XLTrunner]

Take it to Hoover Alignment on East Hennepin. They've been around forever and that's all they do.

 

[markfothebeast]

I'm pretty sure it's the torsion bars. I adjusted them and it appears to have straightened out A LOT. Suspension too low = negative camber. Both sides are out of whack. Youtube video to come.

 

[markfothebeast]

Does someone have the measurement for the stock gap between the top of the stock tire size and the center of the fender lip? I had a one inch difference.

 

[markfothebeast]

I might have that backward. Torsion is a bit different than coil overs that I'm used to. The ride is pretty stiff and tightening the torsion bolt might be doing the opposite with the camber. It appeared to be straightening out but that might be my eyes decieving me.

 

[XLTrunner]

Does someone have the measurement for the stock gap between the top of the stock tire size and the center of the fender lip? I had a one inch difference.

My '98 XLT is sporting stock size 235/75/15 Michelin LTX M/S tires with about 15K miles on them and the gap distance between the top of the tire and the center of the fender lip is over 5". Nothing altered with suspension and stayed with conventional Gabriel Max Control mono-tubes when time came to replace shocks.

 

[SWIGIN]

Don't forget that when you change the camber that you also are changing the toe at the same time.

 

[markfothebeast]

I have fender to wheel gap to about 4-3/8" and it drives and steers much safer. I tried to do a time lapse video to watch if the wheel moved to a more positive camber. However, it won't immediately change without the front being in the air.

 

[markfothebeast]

The alignment shop owes us one... I created a quick time lapse with my camera mounted to see if the geometry changed. This is a poor example, unfortunately. I must have cranked that bolt 15 times counter-clockwise. The ball joints will most likely absorb some of the suspension angle changes before it is visible. Due to more important projects I could not put it on the level concrete surface in the garage.

 

[markfothebeast]

I believe some of the steering and unsafe handling issues are also in relation to that awful sag in the rear. Maybe someone could help me here as I have only a small bit of knowledge on leafsprings. The gap between the rear drivers side tire and fender lip is slightly over 2", about half the distance of the front. Sitting in the drivers seat gives the feeling that you are climbing a hill when not even moving.

What I do know about leafsprings is that there are the springs themselves, shackles, hangers, and clips. I did take a quick peak and noticed broken clips. Is this a fairly important component that aids in the ride height or just absorption? Is it the springs that eventually flatten which causes loss of height?

I'm taking a trip over to the junkyard so I thought about pulling a set of leafsprings but I'd like to know what to look for when inspecting a used set of leafsprings (other than the ride height). Or perhaps an upgrade from another vehicle without raising the rear too much.

 

[koda2000]

I think the clips are there primarily to keep the spring stack from becoming misaligned. Sagging rear ends are a pretty common Explorer complaint along with "the gansta lean" to the left side.

Many here have installed the Monroe shocks with helper coil-over springs with good results. They used to be called Load Levelers, but they may have changed the name.

Here's a link:
http://www.ebay.com/itm/Monroe-Susp...ash=item58d3f79671:g:-hEAAOSwLN5Wjs~M&vxp=mtr

Your other options are to have your springs re-arched, install leaf springs from an F150 or buy new replacements. My guess is that salvage yard used Explorer leaf springs my be just as bad as what you have now.

I don't know that the rear sagging would have anything to do with your front tire wear, but it would be annoying. Alignment and the height of the front will effect tire wear.