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General TR Upper Control Arm Reversed?

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KVH

KVH

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I noticed that my driver's side front upper control arm is stamped: L on the top, and R on the bottom. To me, that means left side of the car, sitting in it, upper rear arm. If that's the case, why is it on the front side of my suspension? The tires on the car are 40 years old. They are Michelin X. The car seems to drive fine and appears unmolested. Is this some error from decades back that never manifested itself in any way? What do you folks feel is going on--assuming I understand what I'm seeing here.
 
Here is what it looks like on my TR6. The R is on the right side/passenger side of the car.

100_4976.jpg


Cheers
Tush
 
KVH said:
I noticed that my driver's side front upper control arm is stamped: L on the top, and R on the bottom. To me, that means left side of the car, sitting in it, upper rear arm. If that's the case, why is it on the front side of my suspension? The tires on the car are 40 years old....
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As Tush points out, "R" for right side, "L" for left side when facing up. If you'll notice, having the longer arm forward pushes the ball joint rearward which gives the suspension positive caster. That's what allows the steering to track straight when there is no steering input.

And what the heck are doing driving on forty year old tires!!! That's an accident waiting to happen!!!
 
martx-5 said:
And what the heck are doing driving on forty year old tires!!! That's an accident waiting to happen!!!
Click to expand...
Absolutely! They may "drive fine" and look fine, but they are prone to sudden, catastrophic failure.

As John Herrera used to say, I have experimented with this. When I bought Stag #1, the tires had plenty of tread although they were clearly pretty old. I tried driving it home that way, but the LR tire suddenly lost most of it's tread and about 2/3 of the steel belt broke away from the carcass. It basically turned into giant flap wheel (like those paint remover wheels you used to see on TV), and flayed off not only quite a bit of paint, but some of the sheet metal before I could get pulled over.

I didn't get a picture of that one, but here's a somewhat similar failure on the Sports 6. Same situation, trying to get it home on tires that were past their "sell by" date. Imagine if I had been going around a corner at the time!

 
Let me clarify. I'm not going to drive on those tires. I only mentioned it because I don't think anyone was messing with, or working on, the front end of this car--maybe ever.

About the stamping on my control arm, since mine is stamped L on one side and R on the other, I guess you're saying they are just interchangeable from side to side.
 
KVH just bought the car, hence no chance to replace tires yet. He certainly knows better than to do more than a pre-purchase test-drive on them.

KVH said:
...I guess you're saying they are just interchangeable from side to side.
Click to expand...

And the visible letter changes depending on which side the part is used on.
 
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