Space Between Tires

[Hot Duck]

I have an M923 and have a question about the space between the rear tires. This is hard to explain, but I am talking about the space between the back of the tire on the front rear axle and the front of the tire on the rear rear axle of the truck (tandem axles). Does this make sense? If you measure the space between the rear tires the gap is not the same on both sides of the truck. Any ideas?

 

[R Racing]

On a walker beam setup I have seen the axles move left and right standing from behind the truck. But not front to back ? If I'm understanding you correctly.

 

[goldneagle]

are all the tires the same? How much off are they?

 

[Hot Duck]

Yes. All tires and wheels are exactly the same. First picture is the driver's side. Seems to be way too close. Second picture is the other side.

 

[R Racing]

Just for grins and giggles did you measure the Dia of you tires to see if there all the same with a tape? and also check center to center measurement of the 2 rear hubs ? If both side centerlines are the same you could have a slightly taller tire .

 

[Castle Bravo]

That looks uncomfortably, if not dangerously close to me.

One thing you could do is make a hard right turn and measure the distances and then make a hard left turn and measure the distances. See if they vary a lot.

It may be a good idea to look at your torque rods too. See the attached photo for that.

 

[M813A1]

check the radius and torque arm bushings you might have some bushing that have worn out or deteriorated !! On the outside chance your truck may have had 2 different length spring installed durning some kind of maintenance and that would give you the same problem ..

 

[Coldfusion21]

Check hub center to hub center, could have some worn bushings or bent/improper parts under there.

 

[powerhouseduece]

check the radius and torque arm bushings you might have some bushing that have worn out or deteriorated !! On the outside chance your truck may have had 2 different length spring installed durning some kind of maintenance and that would give you the same problem ..

I agree.

If the truck has missmatched/worn out dogbones then that could be more likley the problem. Also, one of the axles could be bent. That looks like a huge diffrence between the 2 sides, something is not right. Have you noticed any cupping of the rear tires? I have 1600's on my m818 and have beaten the ever living piss out of it and never had a issue out of it. (proof on youtube)

I would start by checking the dogbones, then check the axle.

 

[Hot Duck]

Ok. I think that we found the problem. The dog bones going from the mount to the rear axle are an inch longer on one side than they are on the other when measured from eye to eye. This is the only possible cause that we could find. Do you guys agree that this is the problem (or at least part of it) and how difficult are these to find? As always, any help is greatly appreciated.

 

[Castle Bravo]

That certainly sounds like it could cause the issue you are seeing.

I don't know if the M939 dogbones are different than the M809 ones, but it sounds like one of yours is incorrect. See if you can find out what the correct length is (Presumably the other 3) and see if you can purchase and install the correct one in place of this longer dogbone.

The specifics of how to do this should be in the TMs and there should be a good amount of information if you search these forums.

 

[dmetalmiki]

could be a reasnably quick fix there...cut to lenth, sleeve, AND weld it. job done.