2.93 Open, or lower posi?
 

I'm close to the point of re-installing the rear end on my 68. It came from the factory with a TH400, AC and a 2.93 open diff. I drove the car with that setup for many thousands of miles from the age of 17 to my early 20's. Always seemed to provide enough excitement and performance for my needs.
But, I've also driven a 69 lemans with a 350/4V and a 3.23 (I think) ratio, TH350 and was surprised at the performance of that Lemans compared to the GTO, the GTO was still faster, but the Lemans would go pretty good.

My goal is a ...let's say, 98 point restoration. The car will see very little street, and very, very little abuse compared to the way I treated it as a kid.


I'm torn ... I know the performance of the car would be considerably better with something like a 3.2? ratio posi ....but, is the cost, and the deviation from the build sheet worth it? This is literally only one of TWO deviations from the build sheet I am considering ...the other being installing the Ram Air exhaust manifolds instead of the typical YS engine exhaust logs.

As much as I love the car, and despite buying it graduation day from high school, I'll probably sell the car not long after I finish restoring it. I'll spare you the "my white whale" psycho babble as to why I would restore it then sell it .... it's not the money of course. Just looking for some input from other people that love GTO's as to how they would feel about a car that was absolutely correct except for something like the rear end ratio ..and open/posi rear end.

My gut feeling is that if 2.93 served me well at 19 years old, it would probably serve me well at 55 years old.
JohnnyB

If you're going to sell it, leave the rear gears as is.

That's something the next owner can change if they prefer. Same with the exhaust. Why change if your going to sell?

Whoever ends up with it isn't going to buy it because it's a race car. Leave the rear alone, I'd say.

Excellent, I'll take that advice and leave it the way it was born.

It will save me time and money anyway :)

Feels to me as if the gears are still decent shape, have not looked at them yet, but not a lot of backlash and they feel smooth and quiet moving them by hand.

Great to have input from a bunch of people that really like these cars as much as I do.

JohnnyB

And... well now that I have that issue decided. What should I do to freshen up a rear end? (No puns please :). I've worked intimately with every other part of automobiles except the rear axle. I know it should have new outboard axle bearings and seals so that's in the plan. What else? Should I just check over what I can based on the service manual recommendations? Anything in particular I should look for? Any known weaknesses, wear problems etc? I honestly don't think the rear lube has been changed since I bought the car in 1976. Never leaked a drop (just a weep from the vent now and then), never made any noise other than a tad of backlash "clunk" every so often.

JohnnyB

Put fresh lube in it, replace the axle bearings and seals.

Other than that I'd leave well enough alone.

If it ain't broke don't fix it. :)