What is the transmission dipstick length?

Tiny
TWEBB101
  • MEMBER
  • 1984 CHEVROLET TRUCK
  • 7.4L
  • V8
  • 2WD
  • AUTOMATIC
  • 169,900 MILES
I'm trying to determine the correct length of dipstick I need for my transmission fluid level. The engine is a 454 and the transmission is a THM400 3-speed. The stick I have now is 32" long, not including the handle. I tried to look online but got varying answers with varying lengths. Can you help confirm the correct one?
Wednesday, November 9th, 2022 AT 12:13 PM

3 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
Hi,

I believe the filler tube is approximately 25" in length. The dipstick would be a few inches longer.

Since GM no longer produces this part, you can get an aftermarket. Even if the filler tube is a bit shorter or longer, the manufacturer has compensated for that in the dipstick. Since we can't be sure about what you have, I would recommend replacing the tube and dipstick together.

I know Mr Gasket makes one for this truck. Here is the part number: 9765A 9765

Check that out and let me know if it helps.

Take care,

Joe
Was this
answer
helpful?
Yes
No
Wednesday, November 9th, 2022 AT 5:59 PM
Tiny
TWEBB101
  • MEMBER
  • 178 POSTS
Thanks! Can you also tell me the amount of fluid needed for a transmission fluid change?
Was this
answer
helpful?
Yes
No
Thursday, November 10th, 2022 AT 12:31 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,755 POSTS
Hi,

Interestingly, the manual doesn't have the specifications for a service. I know it holds 11 quarts of it is totally dry, but that isn't the case when you drain it.

Here is what I suggest. Start by placing approximately four quarts to start. Once you add the fluid, follow the directions I attached below. Also, it doesn't mention it, but I would shift it through the gears before checking the level.

Let me know if this helps.

Take care,

Joe

See pic below.
Was this
answer
helpful?
Yes
No
Thursday, November 10th, 2022 AT 7:37 PM

Please login or register to post a reply.

Sponsored links