abnormal tire wear

hey guys

for about two years ive been getting an abnormal tire wear,, fronts only, on the inner part of the tire , almost like a clamshell shape, every other tread,, now,, my front bearings and steering/ kingpins ,all good ,had them checked, im at a loss, someone mentioned, pulling my front shaft might solve this,any ideas guys?
plus, until i hit 45 mph,, i get a slight shake
thanks
kevin gibson

I had what sound like the same probllem I found that the rubber bushings on the shock absorbers had gone bad but the shock was still good. I put some neoprem bushings from 4wheel parts and that fixed the tire wear. I put a new tire on and so far have not had any more problems.

One can get that wear pattern if the toe-in is off. If the front tires are toed-out to far it is like driving on the inside edge of the tread. The front of the tires should be about 1/8” closer than the back. The measurement and adjustment must be done under load; the tires have to be on the ground. If one doesn’t have turntables a couple of pieces of plywood and some Tyvek, the house wrap stuff, will do. It is best to use new tires properly inflated and to have a helper.
Jack up one side and draw a fine line around the center of the tread with some chalk or a soap stone. Take the Tyvek and cut about a dozen pieces 12”X 12” square and place them stacked under the tire and on some plywood, lower vehicle. Repeat other side. The Tyvek is very slippery and the tires will rotate easily. There is a whole section in the manual on this, but a close enough way is to measure the distance between the drawn lines on the very front and very back of the tires. Adjust the tie rod end till the front is 1/8” closer than the back. It helps to turn the tires after adjustment and before measuring. Once set tighten tie rod end.
As far as a shake or actually a vibration that changes with speed that is usually a tire(s) out of balance.

have you ever rotated the tires? they need rotating just like a car does.

no, when they wear, i throw new ones on,, i went two years without this problem, i put ne tires on, and it started up right away, its telling me, somthings out of wack

A lot have to do with the rear bogie being solidly coupled without a differential, it causes tire scrubbing at every turn of the wheel.
If you spend a lot of time on paved roads, remove the stub axle between the two rear axles and note the difference. Smaller turning circle, better mpg and less tire wear in front....

Scrounger said:

Jack up one side and draw a fine line around the center of the tread with some chalk or a soap stone....

Click to expand...

Excellent advice, however this part should be clarified- Hold the chalk still and rotate the tire to make the line. Also, a board with a small nail can make a very fine "scribe mark" that doesn't actually dig into the tire, but makes a very precice line as well.

I've given this advice before, and been misunderstood or "overruled" due to the ease of not jacking up by using other methods to make the line... Your mark is on the tire, but you're measuring the hub/bearing/spindle assembly, thus the rotation of the wheel is what's scribed on the tire, not an actual tire center line.


I've always been told "loaded only" when doing this, however my tape and my tape says "no difference". I'm going with "set it up however it works, then double check once it's on the ground".

The military has a very cool allignment gauge that measures across the tire treads. A similar and very effective gauge can be made with two C clamps, two framing squares (or similar improvised materials. Hold one framing square so it looks like an "L", and the other so it looks like a reversed "L", and clamp each short end to the two by four. Adjust the width to match the lines on the rear of the tires exactly, then carefully move it to the front of the tires, and measure how far the line is off. With just one person holding/reading the tape, there's a lot less room for "interperitation".

.02

On my most recent truck, When i got it home i noticed the tires were wearing choppy on the outside, when i checked the toe-in with my chalk line as descibed above, I found that the toe-in was off a full Inch! The truck handles much better now!

This is what I use and it works pretty well. Its made from a piece of 3/4" thin wall PVC 54" long and and a 13" long thin wall 1/2 " PVC length that has one end wrapped in masking tape providing for an interference fit inside the 3/4" pipe. I wrap just enough tape to keep it tight but moveable. I marked the outside end with close to 1/8" hash marks with a permanent marker. With two people its easier but I stretch it out to touch the inside of the front tires on the sidewalls at mid axle level first behind the axle and note what marking its near and then move to the frontside of the axle and see how far the 1/2 inner pipe had to be slid in. It should be one mark in to be close to desired. You couild start at the front then do the backside pulling out on the inner pipe. Its not precision instrument by any means but it gets the toe in pretty close. I also drive the truck for a short distance and check it again. I checked my M818 after I got it home from GL I started on the backside and had to PULL OUT the inner pipe over 1/2" when I went to the frontside!! Way toed out. Works on the duece and 5 ton.

Phil

I made a couple of turntables for measuring toe-in, by using two used rear wheel bearings (the cup & cones), from an old truck. I cut 4 each, 8" x 8" pieces of 1/4" plate. Then tack welded the plates to each cup & cone. When the cup & cone are re-positioned under the tire, they allow the tire to pivot easily, regardless of the load.

Point of clarification, if I may add: The line is scribed on the tire to give a true line all the way around it, regardless of the irregularities in the tire. The tires can be out quite a bit. Also, if you take a spray can of light colored paint, and spray the tire center, the scribed line will show up better.

Lee in Alaska

My above post did assume that the alignment was according to spec, of course...

Here is the PS mag description of the toe-in measurement procedure:

http://www.steelsoldiers.com/index.php?
set_albumName=album25&id=ps245_p8_9_toe_in&name=gallery&include=view_photo.php

I would also include new shocks to help reduce the wear, they handle the high frequency vibrations.
I did all of the above and my current tires now have about 5,000 miles on them without any significant wear. In general the tires seem to be used up at a rate of 1/32 per 1,000 miles.

I have experienced shimmy if the front tires are not perfectly matched, so that's something to think about when they are rotated.

Tips and tricks

Do you see all of the above posts?
All the tips and tricks?
Years of knowledge free for you?
Sometimes it's hard for me to believe the amount of practical help that Steel Soldiers has daily on it's web site.
I ran a military motor pool with hundreds of M-series vehicles for many, many years.
I had 25 Special Purpose Vehicle Mechanics working for me. They were good, no, they were excellent. We maintained a 98% VIC (vehicle in commission) rate for 5 years, the best VIC rate in the military.
The big difference between Steel Soldiers and my motor pool is that we had the full weight of government support behind us. We had a 50 vehicle maintenance shop stocked with a couple of million dollars of tools and specific test equipment.
What do the guys on Steel Soldiers have?
Backyard garages, junk yards and lengths of PVC pipe?
I know that some of you have better facilities and tools, but truly none of you have every single piece of gear that these trucks require.
So you make do with what you've got. I'll say it again, lengths of PVC pipe? I am impressed. Most of you know that knowledge is power, most of you know where to find all of the necessary Technical Manuals to maintain your vehicles. But most of you don't have the military Technical Schools and military OJT (On the Job Training) that all of my mechanics had.
What you do have is each other, connected by the Steel Soldiers website.
You have the accumulated knowledge of several hundred enthusiasts who literally know how to git-er-done.
I am not impressed easily, but every day I look at this website, I learn something new.
Think about that. I ran a tactical motor pool for over 10 years and I've owned MV's for over 20 years but I'm learning every day.
You guys are awesome!

RE: Tips and tricks

Sarge,
Boy, well said. I can't believe the knowledge base on SS, invaluable for a MV enthusiast. This site uses the theory of "why re-invent the wheel"!!!! I made a small donation when I first joined and plan on donating again to support this great site!

this is what my wear looks like
kevin

I greatly appreciate the comments on tire wear issue. I have recently purchased an M109A3. I have excessive tire wear on the right front tire on the outside and the camber on the axel is out about 1 & 3/4 inches the left front is out about 7/8 inches and exhibits slightly less wear. the frame shop claims that the steering knuckle bushings do not have to be replaced.
My question is how do you adjust the camber angle on the Rockwell front end axel housing?

Any advice on the matter would be welcome.

What is a normal running temperature for the radiator coolant?