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 06-13-2018, 12:13 PM   #1
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Pinion nut question

Had to replace the pinion seal in my 69 and can't find a nut locally anywhere so I have to re-use the nut. An old timer told me to use some loctite blue and don't over tighten. I need to get this truck back on the road, is there a torque spec I need to follow?
72LB is offline   Reply With Quote
Old 06-13-2018, 01:31 PM   #2
Grumpy old man
Senior Member
 
Grumpy old man's Avatar
 
Join Date: Dec 2013
Location: Gods country East,Tn
Posts: 4,938
Re: Pinion nut question

did you already remove the nut and seal?
Grumpy old man is online now   Reply With Quote
Old 06-13-2018, 01:32 PM   #3
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

yes
72LB is offline   Reply With Quote
Old 06-13-2018, 01:44 PM   #4
Grumpy old man
Senior Member
 
Grumpy old man's Avatar
 
Join Date: Dec 2013
Location: Gods country East,Tn
Posts: 4,938
Re: Pinion nut question

Before you remove them you have to mark the position of the nut then on reassembly you have to replace it back to the original position as closely as possible to try to match the original preload it had before . just tightening it back down can change pinion depth and thrash your rear, it's not as simple as remove and replace.
Grumpy old man is online now   Reply With Quote
Old 06-13-2018, 02:26 PM   #5
Rich69shortfleet
Registered User
 
Join Date: May 2016
Location: Waverly, NE
Posts: 285
Re: Pinion nut question

I was in the same situation a while back. I spoke with a highly experienced and highly regarded rear end guy and he said to simply torque the pinion nut to 150 lb/ft and be on my way. It takes a LOT more torque than 150 lb/ft to crush the crush sleeve so at 150 lb/ft you will not affect the crush sleeve or alter the pinion depth.

One thing that is VERY important is that you clean the threads on the nut and threads on the pinion. Make sure that any and all old threadlocker has been removed and that there are no nicks or damage to the threads. Then, using a quality high strength threadlocker reassemble and torque to 150 lb/ft. If you haven't done so, adding a touch of RTV to the splines on the yoke will help prevent a leak via the splines which can appear like a pinion seal leak in the future.

I have to stress, be sure to clean the threads very well. Leave no residue behind. Did I mention you need to clean the threads? Any remaining old threadlocker can wildly affect getting the proper preload via the torque setting. Don't forget to clean the threads.

I have had to do this three times over the years chasing a leaking pinion seal. I've had no problems with the rear end and it remains as quiet as when it was new. I have hauled and towed plenty with no issues so it is clear I got good advice and have not altered the pinion depth in any way.
Rich69shortfleet is offline   Reply With Quote
Old 06-13-2018, 04:10 PM   #6
57taskforce
Senior Member
 
57taskforce's Avatar
 
Join Date: Jun 2014
Location: Farmington, New Mexico
Posts: 2,134
Re: Pinion nut question

Quote:
Originally Posted by Rich69shortfleet View Post
I was in the same situation a while back. I spoke with a highly experienced and highly regarded rear end guy and he said to simply torque the pinion nut to 150 lb/ft and be on my way. It takes a LOT more torque than 150 lb/ft to crush the crush sleeve so at 150 lb/ft you will not affect the crush sleeve or alter the pinion depth.

One thing that is VERY important is that you clean the threads on the nut and threads on the pinion. Make sure that any and all old threadlocker has been removed and that there are no nicks or damage to the threads. Then, using a quality high strength threadlocker reassemble and torque to 150 lb/ft. If you haven't done so, adding a touch of RTV to the splines on the yoke will help prevent a leak via the splines which can appear like a pinion seal leak in the future.

I have to stress, be sure to clean the threads very well. Leave no residue behind. Did I mention you need to clean the threads? Any remaining old threadlocker can wildly affect getting the proper preload via the torque setting. Don't forget to clean the threads.

I have had to do this three times over the years chasing a leaking pinion seal. I've had no problems with the rear end and it remains as quiet as when it was new. I have hauled and towed plenty with no issues so it is clear I got good advice and have not altered the pinion depth in any way.
This is how Iíve done a few as well. Never had one problem with bearing or gear wear doing it this way.
__________________
'57 3100 350/700r4 35x12.5's
'72 K/20 Cheyenne 350/SM465 http://67-72chevytrucks.com/vboard/s...d.php?t=662879
'98 Silverado LT K2500HD ECLB Vortec 454/4l80E: 6"RCD 315/75/16's
'01 Suburban LT K2500 Vortec 496/4l85E 240,000 and counting- drive train still all original.
57taskforce is offline   Reply With Quote
Old 06-13-2018, 05:14 PM   #7
Rich69shortfleet
Registered User
 
Join Date: May 2016
Location: Waverly, NE
Posts: 285
Re: Pinion nut question

FYI, the torque required to begin to crush a crush sleeve is 225 lb/ft or more.
Rich69shortfleet is offline   Reply With Quote
Old 06-13-2018, 05:52 PM   #8
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

Wow it didn't feel that tight when I took if off. I will clean the threads thoroughly, what about using loctite? Me thinks torquing the nut will be fun under the truck.
72LB is offline   Reply With Quote
Old 06-13-2018, 07:04 PM   #9
Rich69shortfleet
Registered User
 
Join Date: May 2016
Location: Waverly, NE
Posts: 285
Re: Pinion nut question

Loctite is fine as long as it is the high strength version. As far as torquing the nut, hopefully you have an effective parking brake. Applying the parking brake and leaving it in gear (wheels off the ground!) should be enough. And either a long torque wrench or a long helper handle. You need to get the truck as high as you can safely so you have as much room to swing the wrench as possible.
Rich69shortfleet is offline   Reply With Quote
Old 06-13-2018, 07:35 PM   #10
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

I have a yoke wrench so I should be ok.
72LB is offline   Reply With Quote
Old 06-13-2018, 11:52 PM   #11
CastIron
Registered User
 
Join Date: May 2013
Location: Oregon
Posts: 236
Re: Pinion nut question

I've done it by marking the old nut and loctiting back in the same spot. I've also done a lot of them on rwd cars when I worked at a GM dealership. The proper procedure for those (it was a recall with specific instructions) was to just torque the nut. I don't remember exactly how tight it was though.
CastIron is offline   Reply With Quote
Old 06-14-2018, 06:23 AM   #12
Metaldoc
Registered User
 
Metaldoc's Avatar
 
Join Date: Apr 2015
Location: Ayr Ontario
Posts: 804
Re: Pinion nut question

I believe you need a new crush sleeve and torque till you have 10 inch pounds of drag on the torque wrench.
Metaldoc is offline   Reply With Quote
Old 06-14-2018, 09:55 AM   #13
Rich69shortfleet
Registered User
 
Join Date: May 2016
Location: Waverly, NE
Posts: 285
Re: Pinion nut question

Quote:
Originally Posted by 72LB View Post
I have a yoke wrench so I should be ok.
Lucky duck!

Quote:
Originally Posted by Metaldoc View Post
I believe you need a new crush sleeve and torque till you have 10 inch pounds of drag on the torque wrench.
No, not at all if all you are doing is removing the pinion nut to replace the pinion seal. If you are replacing bearings or gears, yes, but not for just removing and replacing the pinion nut.
Rich69shortfleet is offline   Reply With Quote
Old 06-14-2018, 10:56 AM   #14
RustyBucket
Registered User
 
RustyBucket's Avatar
 
Join Date: Jul 2009
Location: Space Coast, Fl.
Posts: 771
Re: Pinion nut question

Quote:
Originally Posted by Rich69shortfleet View Post
FYI, the torque required to begin to crush a crush sleeve is 225 lb/ft or more.
A friend of mine had a drive line shop and used an industrial sized 1" drive impact wrench to crush the new sleeves. He had a touch for just how many times to hit it. Said the sound changed as the sleeve began to crush. Then he would check the pre load w/an inch lb. torque wrench. One of those guys that made everything he worked on look easy. .... unlike ME
__________________
Dad always said, "Son, WISH IN ONE HAND, and ......."
--------------------------------------
--------------------------------------

'71 GMC 1500 SUPER CUSTOM short/step, orig. dk. blue, 350/700r, ps,pb, A/C
'72 Blazer 2wd, ochre & white, 454, tremecTKO 500 5spd. ps, pb, A/C, tilt
'66 Plymouth Belvedere City of Miami cop car clone

'70 Nova 406"sb, 13.5-1, solid roller, Brodix, p.glide/t.brake, back halved, 9" Ford, spool 4.88, cage,ladder bar/coilover, 10.5 tire....... SOLD!!
'67 C10 short/step side mount spare -- shop ornament, needs resto.... SOLD!!
'72 Jimmy 2wd, 350/350, ps, pb, fun driver, lots of bondo & a shiny red paint job..... SOLD!!
'69 Nova 350, 4spd, A/C, ps, p.b, needs resto...SOLD!!
RustyBucket is offline   Reply With Quote
Old 06-14-2018, 11:06 AM   #15
slikside
Registered User
 
slikside's Avatar
 
Join Date: Jun 2010
Location: San Diego Co.
Posts: 997
Re: Pinion nut question

Sub'd.
__________________
1972 Chevy C-10, SWB, Fleet, 350/350, PS, PB, all stock, Survivor.
slikside is offline   Reply With Quote
Old 06-14-2018, 12:36 PM   #16
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

Quote:
Originally Posted by Rich69shortfleet View Post
Lucky duck!
Found it at a swap meet last year, I knew there was a reason I bought it.
72LB is offline   Reply With Quote
Old 06-14-2018, 01:55 PM   #17
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

Torqued it too 150 and it was fairly tight, ended up backing it off a tiny bit and it has around 10 to 12 inch lbs of drag to it.
72LB is offline   Reply With Quote
Old 06-15-2018, 08:45 AM   #18
volksworld
Registered User
 
Join Date: Apr 2011
Location: formerly NY currentlyNC
Posts: 339
Re: Pinion nut question

that 10 inch pounds would be for a pinion gear in a bare case...so if you have a diff , axles and drums there would be a hellava lot more drag....and i sincerely doubt the sleeve "uncrushes" when you backed the nut off
__________________
1970 short step c10 leaf spring 454
volksworld is offline   Reply With Quote
Old 06-15-2018, 09:22 AM   #19
72LB
Registered User
 
72LB's Avatar
 
Join Date: May 2017
Location: Inman, SC
Posts: 143
Re: Pinion nut question

Thats with axles in it, was told to check the drag with tires and drums off.
72LB is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 10:08 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Copyright 1997-2013 67-72chevytrucks.com