[67GP428]

Is there a right and left upper control arm? Or will either one work on either side?

[PontiacJim1959]

I don't know of any difference. They should be equal length. The only difference I am aware of is the 1964 used a different arm.

[67GP428]

The reason I asked. I noticed a R and a L on the upper control arms. Of course mine are on the wrong sides. Thats how they came off the car. Frank's Pontiac parts site shows them as a R and L. Guess what I doing tomorrow?

[PontiacJim1959]

OK, interesting. I would have thought equi-length and same angle going from the crossmember to the rear axle mounts.

I have my '68 Lemans arms out and replaced with aftermarket adjustables, but now I am going to have to take a look at those just out of curiosity.

[Bill Hanlon]

1966 Pontiac Chassis Parts Catalog calls for 2 each Front Suspension Upper Control Arm, part # 9778113 used on both 1965 and 1966 full size Pontiacs with any suspension options.

[67GP428]

All I know there is a R and L stamped on the upper control arms. Like I also said, Frank's Pontiac Parts sales them as a left or right upper control arm. If there's wasn't a stamp. I wouldn't of 2nd guessed myself. I ended up swapped them out.

[mr67gp]

The only difference is likely at the ball joint mount. Probably a different angle in the stamped landing.

[67GP428]

That's what I was thinking. Many other year Pontiac you can see the difference in the right and left upper control arms.

[stevep]

I believe that they are slightly different.

[8LUG]

Originally Posted by Bill Hanlon

1966 Pontiac Chassis Parts Catalog calls for 2 each Front Suspension Upper Control Arm, part # 9778113 used on both 1965 and 1966 full size Pontiacs with any suspension options.

Bingo 9778113 Maybe production line ones had the stamp over the counter did not. Just like a 1964 Ignition coil #187 embossed, Look in the parts book and it shows #134, #187 was the production line coil used.

[389]

Maybe the arms are the same but are the ball joints the same? Maybe they marked them so the tech wouldn't mix the ball joints up.. They used to make one upper control arm attachment point further back then the other for some reason...

[8LUG]

Originally Posted by 389

Maybe the arms are the same but are the ball joints the same? Maybe they marked them so the tech wouldn't mix the ball joints up.. They used to make one upper control arm attachment point further back then the other for some reason...

GP.6.178 1964 p/8 ball joint pkg. 9775241 RH, 9775242 LH Right on the money 389

[8LUG]

Originally Posted by 8LUG

GP.6.178 1964 p/8 ball joint pkg. 9775241 RH, 9775242 LH Right on the money 389

Gave the wrong numbers It's 9781031 RH & 9781032 LH

[63gpman]

Makes sense, production line control arms would have already had the ball joints installed and because the joints are RH and LH, it would have been easy to identify with markings on the control arms than looking for numbers on a ball joint?

[mgarblik]

There is probably a little caster angle built in the mounting surface or housing of the ball joint. Just a guess.