Delmont 88 PA

Does anyone know where you can buy individual internal seals for a TH400? It is a steel oil seal that goes on the input shaft and into the oil pump. It's approximately 1-1/8" in diameter and locks.

The attached picture shows what is left of the original.

Thanks!

matt69olds

You can order individual seals and gaskets thru TransStar. Find a transmission repair shop and ask to look thru the catalog. I'm very familiar with the TH400 trans, they don't have a sealing ring on the input shaft. I haven't had a switch pitch trans apart in a long time, I'm pretty sure those don't use rings on the shaft either. Are you sure this in a TH400 trans?

BILL DEMMER

any decent tranny shop should stock one. you could also try napa.


bill

Delmont 88 PA

The trans is a TH400. I noticed in the factory shop manual that this shaft oil seal ring is listed for 1965 to 1967 only. Newer TH400's probably don't have it.

One picture is to show that this is a TH400 and the other is to show where the shaft oil seal ring (8623296) is located--at the tip of the screwdriver where the pump enters the forward clutch.

Thanks for responding!

matt69olds

Hmm, guess I haven't had one apart that is that old. Learn something new every day!

I would guess the sealing ring has something to do with the switch pitch. Head to your nearest trans shop with the old seal in hand and ask to go thru the spare parts pile (every trans guy has one!) and see if you can find a match.

joe_padavano

Likely due to the switch-pitch converter on the 65-67 transmissions.

Delmont 88 PA

Thanks and I'm learning a whole lot.... So I'm guessing if I get another input shaft and converter (one with a slightly higher stall) this problem will go away?

Delmont 88 PA

Found the ATP part number (JR58) and did a search. Purchased 2 from Amazon.
Amazon for a hard to find item like this! Go figure....

Delmont 88 PA

The seals (got 2 in case I break another) have arrived from Amazon.

What is a switch pitch convertor?

matt69olds

It a converter that can electrically change the stator angle inside the converter to offer 2 stall speeds. Buick, Olds and Cadillac were the only car lines to use it. There is a switch mounted somewhere on the throttle linkage that engages the higher stall speed above 60% throttle opening. I heard it was discontinued due to cost and because the converter has a weird "whirring" noise. I have a friend with a 66 442, I don't notice any noise when driving it so I cant verify the noise.

Delmont 88 PA

Thanks Matt69olds. That would explain the solenoid on the oil pump!