Pitman arm making knocking noise
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Joined: Jul 2012
Posts: 95
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From: West Los Angeles CA
Pitman arm making knocking noise
I took my 72 vette for an alignment and saw that my pitman arm is
Loose also it's making a knocking noise . My question is can It be fix by just tighten or changing the rubber on the pitman arm or is it warn out and need to be change completly ?? Also can it be that the control valve where the pitman arm connects is warn and need to be change ??
Loose also it's making a knocking noise . My question is can It be fix by just tighten or changing the rubber on the pitman arm or is it warn out and need to be change completly ?? Also can it be that the control valve where the pitman arm connects is warn and need to be change ??
Cruising
Joined: Sep 2012
Posts: 14
Likes: 0
From: Pittsburg KS
I am having the same problem, when i have my girlfriend turn the wheel back and forth while I am under the car the noise is definitely where the pitman arm links to the power steering box but I am not sure if i need to replace the whole arm or just purchase bushings or what. I just got my vette a few weeks ago and am far from a car expert. So i am looking forward to this thread being answered.
Le Mans Master
Joined: Jul 2000
Posts: 6,001
Likes: 113
From: Saginaw Michigan
If the pitman arm nut was properly torqued it should NEVER loosen while in use. Somewhere along the life of your Vette the pitman arm was installed and the nut was not tightened to specification.
The specification for the Corvette pitman arm nut is tighten to 140 ft-lbs. If you don't have the equipment (or expertise) to tighten it to spec, trailer it to a dealership or maintenance facility that can.
I question an alignment shop that noticed the loose arm and even allowed you to drive your car with a noticeably loose arm. We are talking about a potential MAJOR safety problem with this condition.
Remove the nut, lockwasher, and the pitman arm. Throw the arm away and purchase a new one. Inspect the splines on the pitman shaft. If they show any signs of wear, you are going to need a new gear or a rebuild of your gear with a new pitman shaft. (The splines on the pitman shaft are hardened, so there is a chance that only the pitman arm needs to be replaced.)
Jim
The specification for the Corvette pitman arm nut is tighten to 140 ft-lbs. If you don't have the equipment (or expertise) to tighten it to spec, trailer it to a dealership or maintenance facility that can.
I question an alignment shop that noticed the loose arm and even allowed you to drive your car with a noticeably loose arm. We are talking about a potential MAJOR safety problem with this condition.
Remove the nut, lockwasher, and the pitman arm. Throw the arm away and purchase a new one. Inspect the splines on the pitman shaft. If they show any signs of wear, you are going to need a new gear or a rebuild of your gear with a new pitman shaft. (The splines on the pitman shaft are hardened, so there is a chance that only the pitman arm needs to be replaced.)
Jim
Drifting
Joined: Aug 2004
Posts: 1,883
Likes: 124
From: Lubbock TX
Is it the pitman arm itself that's loose or the ball joint on the end of it where it attaches to the steering components? It's rare to see the pitman arm loose from the steering box shaft but wear on the ball joint is very common. In either case, it's time to replace it.
They can be a royal pain to remove, I've broken countless pullers trying to get 'em off. Now I use a thin cutoff wheel and cut as far through one side as possible, then stick a chisel in the cut and whack 'er good with a hammer. Once it's broken, it will come off much easier.
They can be a royal pain to remove, I've broken countless pullers trying to get 'em off. Now I use a thin cutoff wheel and cut as far through one side as possible, then stick a chisel in the cut and whack 'er good with a hammer. Once it's broken, it will come off much easier.
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
The description of the problem from the original poster is unclear. With the engine off, the ball stud will move significantly in the control valve and seem loose. With the engine running, the slightest movement of the control valve should cause the assist cylinder to move the wheels in that direction. If the ball stud is sloppy with the engine running, then a control valve rebuild or replacement is in order. If the problem is that the pitman arm is loose at the steering box shaft, then it needs to be removed and inspected to see why. If the ball stud to the control valve is loose in the pitman arm, that is a tapered hole that will need the ball stud removed and check for wear on either the shank of the stud or the tapered hole in the pitman arm, then repaired or tightened up.
Cruising
Joined: Sep 2012
Posts: 14
Likes: 0
From: Pittsburg KS
On my car it is the pitman arm at the steering box that is making the noise. And I will order a new pitman arm and inspect the steering box gear. Thanks I just joined this yesterday and is proving to be quite helpful.
