Dynaflow info needed

Buddy has a 1964 Bonneville with a 389 and Dynaflow transmission. Does anyone know of a place to get parts to rebuild it or an adapter to use a different more common auto transmission? Local ****** shops are quoting 2800 and up to rebuild. Thank you for any help.

 

Your buddy has a rare car there as Pontiac never used the Dynaflow trans. The last year for Dynaflow was the '63 Buick. It should be a Hydramatic...pre Turbo 400. Frank

 

Actually it's probably a powerglide...

 

Slim-Jim

 

10-4 on the slim-jim. I think they were called a ?? ROTO-MATIC??It's been 25 years since I had one of those apart. As I remember right they didn't have a torqe convertor and had a bunch of steel tubes that just pumped fluid around inside. Maybe I am dreaming ,it was along time ago.

 

Thanks for the replies, I appreciate it. I went and saw the car today and the pan is a square and has 14 bolts holding it on. It also says hydroMatic on it. It has 3 forward gears on the shifter. Thanks again for any help ID'ing this transmission.

 

Got it. Roto Jetaway. Thanks for all the help. Much appreciated!!

 

The roto-Hydramatic, or slim jim, was NOT used in a Bonneville (although I suppose it's possible someone swapped one in at some time in the past.) The slim jim was used in the Catalina and Ventura, while the Bonneville and Star Chief used the Jetaway, which was a four speed Hydramatic. They're two totally different animals. The shift indicator on the dash is labeled P - N - Dr - L - R, but there are indeed four speeds.

Parts are expensive and it's hard to find someone who knows how to work on them, but they are good, strong transmissions. If you do decide to swap in a newer transmission the usual problem is that 1964 and earlier Pontiacs had the starter bolted to the transmission, while 1965 and later had them bolted to the engine block. However, you may be in luck...most 1964 engine blocks had mounting holes in the block for a starter even though they weren't used. Pull the starter and check the block - if the holes are there you can bolt in a TH400 and use a later style starter. You'll still have to make some modifications to the transmission mount on the crossmember and probably some modifications to the driveshaft.

 

The shift quandrant should read PNDSLR or PND4D3LR. It should be a dual range dual coupling JETAWAY. Parts are available and there are people that will rebuild them, look on other posts or do a search. It is not the worse trans, nor the best. I go along with swapping it out for TH400.