Death of a slimjim - how to fix?

I'm told my auto trans behind the 389 in my '64 Catalina is called a slimjim. Shifts real nice and smooth - or at least it did until it..just stopped working at a traffic light.

Now everytime you put into drive the motor dies. No nasty noises or anything.

You can drive backwards as much as you want

A friends Dad has been rebuilding transmissions for 54 years and done plenty of these, but he's 14 hours away from me in Maryland.

So, possible choices:

1. find someone around Atlanta who can rebuild this (sounds expensive)
2. find another slimjim
3. find another transmission that'll fit?

Any ideas?

 

Up until 65 GM lines each had their own bolt pattern so the standard BOP pattern won't fit your engine.

I have seen early hydros in the classifieds cheap or free before, you might put an add in the wanted section.

I have a '63 Grand Prix with the slim jim hydro, so far so good with it but have researched the tranny thing pretty well over the years. As far as I can tell you have to go back original, or pay a lot of dollars for an addapter. www.transmissionadapters.com has a kit to use a later GM but it's not cheap.

You have checked to make sure something didn't come loose on the linkage, haven't you. I ask, because mine would die when coming up to a stop sign, like it was binding up and lugging the engine down. It was just a linkage adjustment.

Good luck.

GV

 

Considering what you're probably going to pay to have it rebuilt, I'd get an adaptor and go with a 700r4. Nice low 1st gear, and you've got overdrive.

 

A person you can trust 14 hours away might actually not be a bad approach...swap will clearly be expensive, having something old and strange rebuilt by someone you don't know is chancy.

 

A couple of ideas for you. My friends salage yard has a few slimjims. Some are out and stored some are still in there original cars. I am there often and could bring one back to MD so your old man could go through it. Then you just coordinate getting the known good and exact replacement down to you.

 

"Now everytime you put into drive the motor dies. No nasty noises or anything."

my 62 Caddy would do this from time to time. it turned out that the trans wasn't downshifting at a stop sign like it should. so you would stop and the trans would still be in high gear. I "fixed it" by manually shifting down to low and taking off that way.

 

64 was the first year pontiac cast a provision in the block for a starter and used the common b-o-p bolt pattern, but they still used a bellhousing mounted starter. I've changed a couple to 400 turbo's. you need a 65-up starter and flywheel,if you get a long tail trans a 68-72 lemans driveshft fits perfect.weld a new pad on the crossmember for the mount. A couple of spots on the trans tunnel will need to be hammered for a little clearance. The linkage will need some fab work but not that much. Good luck

 

Since you have the BOP pattern I would recommend going with the TH400 or 700R4 transmissions. They are much better boxes than the slimjim will ever be.

 

Yup, with a '64 you're in luck as it has provisions for a block mounted starter. It's fairly straightforward to swap in a TH400 or TH350. You probably will need to clearance the trans tunnel a bit with a big hammer in a few spots to clear the TH400.

First, make sure all the trans linkage on the slim jim is connected and working properly, including the kickdown linkage to the carburetor - I remember the '61 Catalina I drove back in college had a problem one winter when the linkage underneath the car got ice in it and the thing wouldn't shift....I had to drive home in first gear. The next day it got warmer, the ice melted and it worked fine again.

 

1. Remove from car.

2. Bolt to chain.

3. Attach other end to boat.

4. When you need to stop the boat, throw transmission over the side.

Problem solved -

The "Slim-Jim" was known for problems and premature failure even when new. It seems with those Pontiacs either the frame rotted out or the transmission blew. I've run across cars parked for both reasons, sometimes even side by side.


I would slip a 200R4 in the car, personally, just to get the OD and have a 4-speed trans. The early 389s like a 4-speed. And it should be a relatively simple upgrade. But as noted a long tail 400 is a near bolt-in, and doesn't give you the kickdown control to mess with.

 

This is what I did to my 64. Had to clearance the tunnel a bit and just used a plate bolted to the original crossmember to move the mount forward to fit the TH400. I used the TH400 shift linkage, but had to narrow it a bit. Also had a new driveshaft made, but if you can find the Lemans driveshaft, that sounds like a quick fix there.

 

if you do try to have your friend fix it... keep in mind that shipping will be pricey and probably 3 out or 4 transmissions we ship UPS come back damaged. Pack it well... and cross your fingers if you do ship it!

 

Thanks Guys for all your help. rc, thanks for the kind offer.

buds56 & drdave - great to hear from people who've done the work. I'll probably go this route, but money is tight again so it'll probably be sitting a while now

 

I have a '63 Catalina and was wondering what tranny I could use instead? From this thread it would appear that it may be more difficult as the '63 does not have the provisions for a block-mounted starter?

Any info would be a great help. The Slim Jim works, but leaks and the car sat for 25 years before I bought it.

 

my buddy has a rebuilt one out of a 64 grand prix for 125.00
his buddy brought the car home and put a 428 with a turbo 400 in it.
its been sitting for about a year.
he goes back and forth between cleveland and florida all winter.
maybe he could meet you somewhere with it on his way down.

 

4 speed! End of problem

 

Something to try is an old use car salesman's trick.. put about a 1/2 cup of brake fluid in it and see what happens.

My ex-father-in-law had an old Dodge car he bought that wouldn't shift out of first gear when he got it. Added a half cup of brake fluid to it and was able to drive it for about 6 months until the tranny went out.

As others have said, I'd look into swapping to a 700R4 and be done with it. They can be had cheap enough, and if you know what you're doing, you can pick up an entire car off of Craig's List or Ebay for a small fee, get what you want off of it, and then sell/part out the rest to get your money back and wind up with a freebie tranny when finished.

 

Roadracer, I'm in Griffin, and all my years I've liked the Pontiacs from the 60s, but stayed away from them because of the SlimJim's reputation. But here's my thoughts on this deal of yours if you should decide you want to try a rebuild on the SlimJim.
My son, who lives here in Griffin also, works @ Delta and knows a guy, also an aircraft mechanic @ Delta, who builds auto trans on the side, and my son tells me he is good. The guy lives in the McDonough area.
If you like, I can get my son to get contact info and I can pass it along to you.
Let me know if you're interested.
Dave
Dave

 

Rusty is right...these things were born DEAD !!!

 

61 and up use the common b o p bolt pattern, but 61-63 need another starter bolt on option. Wilcap and Bendtsens both make an adapter to mount a newer trans or if you have access to a machine shop build your own adapter from these plans.