68cutS

My father restored this car when i was born in 1985 and it still looks great. Since then he has passed and I really want to pursue what he was going to do. Ok, I'd really like to change out the 2 speed auto to a 4 speed manual and change gearing or rear end to lower gears. This car has to have very high gears as it is now. What all is needed for the trans swap along with components (trans number, part numbers, difficulty in accomplishing etc.) and components to change to 3.73 or straight swap of the rear end. I'm open to all suggestions other than selling the car ha. It's one of those cars that will live in my family as long as I'm alive and hopefully there on out. I'm not the best mechanic but I do pretty well. Thanks guys, I'm happy to be apart of the forum now.

Jared

L69

Look up my thread project basil
It's a full 4 speed swap from a 2 speed I did on a 66 but it's all similar. Grab a chassis manual read the forum and post when u got questions

Rallye Sally

L69

https://classicoldsmobile.com/forums...-400-swap.html

don71

Welcome to the site.

The biggest hurdle to a manual trans is having the crankshaft drilled for a pilot bushing/bearing..the correct one, not an adapted version. Getting the parts is the easy part but still require some effort. Doing the work or having it done is another.

Having your rear diff changed is another hurdle. I think you might consider this one first.

You can have your current rear swapped out entirely with what you want for your goals, or just the parts inside. This all depends on parts availabilty and budget.

I think changing the rear gearing will improve your opinion of the car (make it more fun) very quickly and you can do the trans swap later.

None of this is cheap but might give you a leaping point to start from.

When you get a chance, upload some photos of your car, or share some more about what you goals are.

L69

I forgot. Didn't see the 1 post. Welcome Jared. Were all here to help. And as don71 aid the 4 speed swap is very involved especially the sourcing of OEM parts. And it's expensive expect to pay at least 2500 just in parts. Also the issue with drilling the back of the crank to accept either input shaft bearing 7109 or a bronze one. It's a bear to do in the car. Ur better off making it a 3 speed auto something like a turbo 350. Easy swap

Indy_68_S

What rear gears are in it now ? A lot of JetAway cars had a decent rear to make up for the JetAway as its first gear is closer to normal 2nd gear.

z11375ss

If you're going to a manual, why not put in a Tremec?

Stevec

Jim, does your crank need to be drilled with the tremec or is there a way around it with the modern manual transmissions?

67442nut

A $20.00 1968 assembly manual from ebay will have
a detailed pictorial breakdown with part numbers
on assembling the manual transmission set up.

joe_padavano

ALL manual transmissions require a pilot bearing in the crank. An Olds motor originally bolted to an automatic will not typically have the crank drilled for this pilot bearing.

z11375ss

Check, check, double check. Crank must be drilled. I changed cranks and went with one from a 4 speed. It's pretty involved. But, if you really want that clutch, it can be done.

Stevec

I had my motor built by by a well known engine builder and never asked or checked before putting the engine in the car. I would love a manual transmission but I don't know about cutting a hole in the floor and I don't feel like removing my auto transmission to to check the crank.
The cars been running so good I like the fact I can jump in and cruise. Lol
Would be insane with a 5 speed tremec...

z11375ss

This ^ is why you shouldn't do it. Enjoy your car. I was redoing basically everything at the time mine was installed. It ran really great for a 350/350 combo. Very dependable. Boring as all git out though. Ever since I was a kid I wanted a 4 speed GM A body. I like them all but am very partial to Cutlass.
Now, maybe over the wintertime...................