-2 degrees of caster?

[bobc455]

Title pretty much sums it up. Took my '69 Special in for an alignment, the right wheel had -2.1 degrees of caster and that is the closest he could get. Left wheel had -0.6.

This is a good mechanic that I trust, and have known for years.

He mentioned the possiblility of a bent spindle... is that possible? Seems that might be possible on today's value-engineered cars, but back then the General used some pretty beefy stuff.

If it's worth anything, it used to be a 4-wheen drum car and I converted to front discs with a kit (including spindles) from Stainless Steel Brakes.

Thanks!

-Bob Cunningham

[Bob]

I had a Corvette that had a similar problem. When we looked closely it had been in a bit of a bender and we had to do a bit of bending on the frame brakets to bring things back into alignment. No problem once we figured it out!

[bobc455]

You think it's time for me to visit a frame shop?

-Bob Cunningham

[Bob]

With carefull examination we were able to see our our damage, it wasn't much. Then we did a bend ourselves which brought it right back into the spec area. Not something everyone might like to try, but with understanding what the problem is you might not need a frame shop. If you can find the problem, it might be worth talking to them.

[bobc455]

Thanks.

I am pretty good at the engine stuff, but when it comes to frames, frankly I'm way out of my league. I'll bring it to a shop and see what they say.

-Bob Cunningham

[BadBuick]

Caster is measured by drawing an imaginary line through the upper and lower ball joints (in your case). Negative caster means your upper ball joint is closer to the front of the car than the lower and generally means less steering stability. I don't know the specification but take a close look at your control arms and try to see why your upper ball joint is further ahead of your lower ball joint, especially on the right side.

[bobc455]

Bad,

I stared long and hard at the whole thing, and couldn't see what was wrong.

I have an appointment with an alignment/chassis specialist tomorrow who will check out everything including the frame.

Thanks!

-Bob C.

[62BuickFan]

I have an old service manual that has the alignment specs for these cars and it gave the caster in negative degrees. It said 2.25 degrees negative caster. That seems backwards to what cars are today. In your case, I would check the shims on the top A arm. It may have been rebuilt, and they didn't shim it correctly after that.
One thing is that if you are running radial tires, and I would expect that you are, you will want to put in more caster than what the old specs did anyway. You should shoot for around positive 2 to 3 degrees. Radial tires like more caster than old bias ply tires. Think of caster as the same thing as a fork on a bicycle. That slant of the fork is caster, and that is what gives you directional stability. It keeps the car from wandering at higher speeds. Big road cars like Mercedes have up to 14 degrees positive caster. That way they can run the autoban at 100 + mph with one hand on the wheel.

[tech jake]

I wouldn't worry about caster too much. It will not wear tires. Only camber and toe will cause tire wear. If you have a non power steering car you want caster around 0 or in the negative a little anyway. If the car has power steering you want the caster in the positive reading. The only bad thing is caster can make a car not want to return to center coming out of a corner. If the caster is too negative it might want to wander down the road. If the car drives down the road good without any noticeable problems I wouldn't worry about it.