Step Van HELP

OK guys, I am looking at a step van (Bread truck) for my business. It is a 1979 Grumman with Chevy chassis,350 engine,400 transmission,duels in back . It has new tires all around,new front a arm and tierod end. And new brakes. The only thing I am worried about is one thing when I test drove it. It ran fine and drove fine up to about 50 MPH. Then the front end started shaking thru the steering wheel. It would quit when you slowed down below 50 mph. And occur again when you sped up. I did notice that one of the wheel weights have come off of the wheel recently I think, as there is a indent in the tire where it looks like one has been and the rim shows a mark also. I am just wondering if this tire is off balance, will this occur ? I checked the both front wheels and I can't find anything loose but it is kinda a concern and the current owner knows it is a concern of mine. He says that the front end had been worked on and when it was parked 2 years ago, he swears that it wasn't doing it. He had a home constrcution business and used it to haul insulation. Does anyone have an ideas and how much $ it might cost me is it isn't the tires ? I do not think it is the steering box as it doesn't really take off on you from side to side, just starts shaking. Thanks so much, Raz

From my experience, if it's directly related to speed, it's most likely a balance issue. That does NOT mean that it's the _only_ problem. If there are problems with the tie rods, shocks, control arms, ball joints steering linkage or anything else between the tires and the steering wheel (even a bulge in a tire or bad wheel bearings), a simple balance problem would only exagerate it.

If there's a slight wobble, vibration or shimmy when you hit ~50 mph, and it goes away at 65+ mph, it's probably just the balance. If increasing speed above 50 mph makes it even worse, or if the shaking is violent at ANY speed above 50 (or gets progressively worse as speed increases) you're probably looking at some very expen$ive repairs on any number of components. The only way to be sure what you're looking at ($$$ wise) is a hands-on inspection, but this is what I usually tell friends who ask about shimmys & shakes in front ends.

There is one other thing about heavy trucks a lot of people might not consider. They're not designed to handle or ride even 'close to decent' empty. I've had plenty of big trucks that rode like crap empty and didn't even steer anywhere near as well as they did loaded down. They're OK for transport empty, but can actually 'settle down' really well under load. Just something to think about if the shaking is really minor. If it's anywhere near violent, it's not supposed to ride like that empty or not.

Good luck, - Jeff G

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