Quote:
Originally Posted by wwestman
New 2020 Coachman Sportcoach with Frieightliner chassis. On our first trip and noticed when driving down the freeway the steering does not track well. If I hold the wheel steady, it starts to drift to one side, when I correct and then hold steady it goes the other way. Seems I am always chasing the tail of the dog. Noticed it when we first picked it up, but did not think it was an issue until I had been on the road for a few hours.
Can not think that it is supposed to be like that. No other vehicle I have driven has danced around like this. Can't be good for the front tires.
Tires are correctly inflated. Is this normal? Any ideas what I need to do?
Thanks
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wwestman,
I think it may be normal because the most likely cause is that the new ball joints are too tight yet. Our Leprechaun did this too until we got over 2k miles on it.
I had a similar, but worse experience with this problem before, when I bought a low mile "pre-owned" 2000 F-250 diesel pick-up. It had brand new ball-joints on it, a plus, but they had not been installed according to instructions, a bummer. They were poorly installed by a well known local tire dealer who should have known better. Tightening the joints out of order during installation caused them to bind an excessive amount.
This "installer fault" problem doesn't cause "loose" wandering so much as it fails to caster back to dead center by itself. The steering drag is simply too much for the planned natural tendency to automatically caster straight ahead with normal caster settings. That is precisely why we have caster, for self-centering. Because of the drag of new, or improperly installed ball joints, the steering locks into whatever the last steering wheel input was... fine until the road causes a slight change in wheel direction (bump, groove etc) and then the stiff steering takes off in this new direction... until the driver resets the direction again. Very tiring to drive.
When I figured it out, I was willing to pay this original installer to correct this fault but the shop manager never understood and actually said all F-250's are like that, even his own. WRONG. I gave up on him and was able to prove it to myself several ways and better present this for the next shop.
I found a ball-joint update from an after-market supplier of steel-on-steel joints that accentuated the necessity to do the installation in order because it is a common problem with unknowing shops blaming the joints. Besides Ford, Dodge was the other truck that had the problem (all diesels are so heavy in front, they drag more and wear faster).
I also found an update from Ford that specified that, on problem vehicles, the steering should be checked for drag by jacking the front axle off the ground and pulling (turning) the steering wheel with a scale, engine off. Unfortunately Ford gave no spec on tension, but I found another way to verify the problem.
I found a reference too, that Ford had purposely designed their OEM ball joints without zerks because they used a special nylon cup instead of steel-on-steel ball/cup contact. They did this because the nylon turned much easier, but then there was no grease passage to lube them through the nylon. IIRC, Ford's OEM ball joints were designed to last at least around 80k miles or so which is a pretty good life for the trade-off.
The (other) way I verified the problem was that I also owned a 3/4 ton 2000
Excursion with an identical axle (but V-10 engine). My
Ex was steering good yet, but had a slightly loose passenger ball joint. As a matter of trivia, I figured out the likely reason that right-side joints usually wear faster is because the road crowns that way, putting more leaned weight out there. Anyway, at 120k miles, my Ex still had serviceable OEM joints yet and steered perfectly.
With a simple spring fish scale, the Ex measured 5# of drag. The lousy-steering F-250 measured 15# with the same scale. I had a regular truck shop loosen and reset the F-250 joints in the right order. It helped immensely that the truck shop was aware of the "order" problem and knew what they were doing and why. The end result was that the F-250, with broke-in steel-on-steel joints, then had about 8# of drag and steered much better... with normal caster settings. Voila.
This is a common problem with owners that are pretty proud they bought steel-on-steel replacement ball joints with zerks instead of those "cheap zerk-less factory Ford joints". This is sometimes an error since their trucks may never steer as good again. I see many owners end up buying all sorts of useless expensive suspension doo-dads to try to get the truck to steer right. In some cases, a savvy shop will set the caster way up to overcome the excess drag, but this introduces other problems.
I did finally replace the OEM joints on my Ex. All I could get OEM, were lowers, but it now steers almost as easy as it did when the joints were worn out. As ball-joints wear, the balls keep centering in the cups under weight, so even worn joints work pretty good and maintain alignment. But worn too far, they will eventually fall apart, so it is eventually a matter of safety. Whatever you decide, good luck to you. My guess is that your steering will get better as they break-in.
Wes