The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-19-2012, 11:13 AM   #1
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
1972 Chevy - Transmission Leaking

Okay, pretty sure the front pump seal is shot, when you drive it there's spots on the ground. To me, that's a given.

SOO, we're going to pull it out and put a front pump seal and tailshaft seal in it. Any other seals you can think of to put in while it's out?

Otherwise, I haven't taken the transmission out of this truck yet and am looking for any tips.

Is it a 4 bolt main? I've did the same on a powerglide and think that the procedure should be the same.

Trans shift lever
Vacuum lines
Rear Trans Mount (xmember?)
Front bolts
Drop........

Sound right?
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 11:49 AM   #2
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,594
Re: 1972 Chevy - Transmission Leaking

Quote:
Originally Posted by PLANETGETLOW View Post
Any other seals you can think of to put in while it's out?
Good time to replace the dipstick o-ring. If it's same as mine, you'll need a #113.... 3/4" OD, 9/16" ID, and 3/32" thickness.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 10-19-2012, 11:55 AM   #3
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

Okay thank!

Does everything else look right regarding removal?
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 12:01 PM   #4
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,594
Re: 1972 Chevy - Transmission Leaking

Can't help with that, sorry.... I've never had to pull the trans.


Give it time, someone else with experience will jump on here.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 10-19-2012, 12:12 PM   #5
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

Thanks for your feedback
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 12:26 PM   #6
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,594
Re: 1972 Chevy - Transmission Leaking

No problem. BTW, I have some extra dipstick o-rings... if you PM me your mailing info, I'll send you one.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 10-19-2012, 02:24 PM   #7
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

Quote:
Originally Posted by Stocker View Post
No problem. BTW, I have some extra dipstick o-rings... if you PM me your mailing info, I'll send you one.
Right on brotha, let me see if I can get it local before I waste your time?
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 02:41 PM   #8
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,594
Re: 1972 Chevy - Transmission Leaking

Yeah, they're cheap & easy to find. I spent more time figuring out which size to buy (the one I removed, which had been leaking, was one size too small). I bought a pack of ten and only used one..... The offer stands though.
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 10-19-2012, 03:33 PM   #9
asolde
Registered User
 
asolde's Avatar
 
Join Date: Apr 2012
Location: Henderson Nevada
Posts: 804
Re: 1972 Chevy - Transmission Leaking

Down shift seal also and the shifter shaft seal.
asolde is offline   Reply With Quote
Old 10-19-2012, 03:37 PM   #10
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

So.........

Replace:
Front Pump Seal
Dipstick/Speedo Orings
Downshift and shift seal
Rear Tail Shaft seal

What about the pump bushing?
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 03:54 PM   #11
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,930
Re: 1972 Chevy - Transmission Leaking

How many miles are on this transmission? If it's the original 40 year old TH350... might be wise to just have it rebuilt.



Gary
__________________
'cuz chicks dig scars...

My 1972 GMC 1500 Super Custom (Creeping Death) "long term" build thread.

The Rebuild of Creeping Death after the wreck

Quote:
Originally Posted by LONGHAIR View Post
I would never rebuild a 305.
Quote:
Originally Posted by prostreetC-10 View Post
I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
Quote:
Originally Posted by Marv D View Post
Remember Murphys 2nd law of mechanical relationships... "OPPOSING COMPONENTS ATTEMPTING TO OCCUPY THE SAME SPACE, AT THE SAME TIME, GENERALLY END UP OCCUPYING ADJOINING SPACE AT THE BOTTOM OF THE OIL PAN"
Quote:
Originally Posted by cableguy0 View Post
Its cheaper to listen to advice given when you ask for help than it is to ignore everyone and wait for carnage.
GASoline71 is offline   Reply With Quote
Old 10-19-2012, 03:57 PM   #12
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

No, it's been rebuilt and shifts GOOD. It was my grandpas and it sat for a while, we just started driving it daily and now she's leaking
PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 04:54 PM   #13
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

I found this image, looks like the smaller seal that goes around the output shaft, O-ring behind the pump, and the others mentioned

PLANETGETLOW is offline   Reply With Quote
Old 10-19-2012, 07:05 PM   #14
kaycee
Registered User
 
kaycee's Avatar
 
Join Date: Jan 2000
Location: Wyoming USA
Posts: 2,445
Re: 1972 Chevy - Transmission Leaking

Gotta take the starter out and drive shaft ,take the flywheel/flexplate bolts
out allso,plus the bell housing bolts.
__________________
2001 Silverado K-1500
2005 FXDWG stage3
69 CHEVY Short/Step 327/4L60 373 posi
63 IMPALA 327
kaycee is offline   Reply With Quote
Old 10-19-2012, 10:54 PM   #15
dracula4999
Registered User
 
dracula4999's Avatar
 
Join Date: Mar 2010
Location: Shawnee, OK
Posts: 63
Re: 1972 Chevy - Transmission Leaking

Shouldnt have to pull the starter...i never have
__________________
71 GMC long bed
70 Chevy short step
71 Chevy K10 long bed
dracula4999 is offline   Reply With Quote
Old 10-21-2012, 02:09 PM   #16
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

I can only hope somebody is online now that KNOWS which direction the O-Ring (#4 Pictured above) goes. On one edge there is a beveled edge with a blue mark and on the opposite edge it's flat and just black.

Which way does it install? The beveled edge out (towards the transmission) or beveled edge in (towards the pump)
PLANETGETLOW is offline   Reply With Quote
Old 10-24-2012, 03:32 PM   #17
PLANETGETLOW
Registered User
 
Join Date: May 2008
Location: California
Posts: 161
Re: 1972 Chevy - Transmission Leaking

Well, the beveled edge goes out....

To remove the tranny on a 72 long bed you have to:

Remove the driveshaft at the axle, unbolt carrier bearing
Unbolt rear transmission on Xmember and Slide X-member back
Unbolt Torque Converter from Flywheel
Unbolt transmission lines, speedo cable, and vaccuum lines
PLANETGETLOW is offline   Reply With Quote
Old 10-24-2012, 09:24 PM   #18
mrh33916
Project '67 454
 
mrh33916's Avatar
 
Join Date: Jan 2009
Location: Columbia SC
Posts: 283
Re: 1972 Chevy - Transmission Leaking

I'm not a tranny expert but i did just do this to mine. The only seal I didn't replace before I put the tranny in after it sat was the #4 o-ring, turned out it was dry rotted. You'll want the #6 gasket too (my replacement looked slightly different from the one that was in there but worked fine, just make sure you line it up the way the old one comes out)
You need to stand the tranny strait up before removing the pump housing so the clutches don't fall out. Also mark the case and pump housing before you separate them.

I was told not to take the pump apart or I would need an alignment tool to put it back together.

And yes the blue line goes out.

Good Luck,
__________________
67 C-10 SWB Fleetside 454 (current project)
99 Crewcab SWB Dually 454
75 Datsun 280ZZ430
94 Formula 232LS 454
mrh33916 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 02:22 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com