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 > General Truck Forums > Engine & Drivetrain

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-21-2018, 03:32 AM   #1
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Replaced pinion seal but did I do it right?

After reading and watching videos I replaced a leaky pinion seal today. It was super easy if I did it right.

Marked the yoke, nut and housing, then counted 1-1/2 threads showing so I'd know how far to go when putting it back together. I pulled the nut using an impact so I can't say how tight the nut was but it zipped it off without a problem.

When I put it back together I used a 1/2" drive ratchet and ran it up til the marks were lined up and 1-1/2 threads were showing past the nut, same as before. I felt a little resistance but I never felt the nut get tight. Almost snug maybe but nowhere near tight. I'd say it was similar to setting a crown nut on the spindle after changing a wheel bearing - except using marks and threads as a guide.

I know it's critical to set it right but for some reason I thought it would be tighter.

This may be a dumb question but does my description of the reassembly sound right? If not what should the nut feel like going back on?


Thanks
BigRandy is offline   Reply With Quote
Old 05-21-2018, 06:56 AM   #2
homemade87
Registered User
 
Join Date: Apr 2010
Location: Guntersville Alabama
Posts: 949
Re: Replaced pinion seal but did I do it right?

Best way is to mark pinion verse nut . I did not see where you marked the pinion . I take a Sharp chisel and mark the pinion and nut . Yoke to housing can move and give false reading . If you can still turn the nut buy a ratchet it is still to loose . I usually have to hit it a couple times with a impact to get the marks to line back up .

At this point I would tighten it as much as you can with the ratchet . Counting threads don't get it . We are only talking 1/8 of a turn difference if that to be correct . Then bump it with a impact or with a breaker bar . Most will tighten it past about 1/16 of a turn past the original .
homemade87 is offline   Reply With Quote
Old 05-21-2018, 09:01 AM   #3
Alex V.
Registered User
 
Alex V.'s Avatar
 
Join Date: Mar 2013
Location: Campbellsville, KY
Posts: 877
Re: Replaced pinion seal but did I do it right?

The few I've done, I used the same process but they were older axles with plenty of miles on them so I tightened the nut just a hair past where it had been. That's been at least 10K miles ago (more like 40K on my C3500's FF 14 bolt) and they're still running quiet.
__________________
Alex V.
------
1967 C10 Suburban, 350/NP435, Green/Green, PS, PB, HD cooling, charging, shocks, and springs.

1985 GMC C3500 SRW, Sierra Classic, 454/TH400, white/blue.
Alex V. is offline   Reply With Quote
Old 05-21-2018, 02:06 PM   #4
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by homemade87 View Post
Best way is to mark pinion verse nut . I did not see where you marked the pinion .l .
I left that out by mistake but I did mark it. Even though it didn't feel right I put it back like it was because that's what I thought I was supposed to do. I'll pull the driveshaft and snug it up some more but I'm entering uncharted water since I don't know how much is too much.
BigRandy is offline   Reply With Quote
Old 05-21-2018, 04:04 PM   #5
Bigdav160
Registered User
 
Bigdav160's Avatar
 
Join Date: Apr 2011
Location: Klein Texas
Posts: 2,986
Re: Replaced pinion seal but did I do it right?

That nut will feel tight when it's back into it's original position. This is the point where it's trying to compress the crush sleeve.
__________________
My Classics:
'72 K20 Suburban + '65 Dodge Town Wagon
'72 Corvette Roadster +'67 Corvette Roadster
'73 Z-28 Camaro
'63 Ford SWB Uni Pickup
'50 Ford Coupe
Bigdav160 is online now   Reply With Quote
Old 05-21-2018, 05:47 PM   #6
cadillac_al
Registered User
 
Join Date: Oct 2013
Location: Maine
Posts: 1,539
Re: Replaced pinion seal but did I do it right?

I think the nut should be fairly tight. The pinion depth is set by the shims isn't it? I'm not an axle guy but I have replaced a seal or two and I tightened them to roughly 50-70 ft lbs.
__________________
76 Chevy K20
76 GMC K15
77 Chevy C10
cadillac_al is offline   Reply With Quote
Old 05-21-2018, 09:27 PM   #7
Bigdav160
Registered User
 
Bigdav160's Avatar
 
Join Date: Apr 2011
Location: Klein Texas
Posts: 2,986
Re: Replaced pinion seal but did I do it right?

The depth is set with a shim but the bearing preload is set with the nut compressing a crush sleeve. The nut is self locking.

The effort to crush the sleeve is significant. I would estimated hundreds of pounds of torque on the nut to crush the sleeve.

My technique is using an 1/2 impact and watching the point at which the socket meets resistance. This is the point the nut came off.
__________________
My Classics:
'72 K20 Suburban + '65 Dodge Town Wagon
'72 Corvette Roadster +'67 Corvette Roadster
'73 Z-28 Camaro
'63 Ford SWB Uni Pickup
'50 Ford Coupe
Bigdav160 is online now   Reply With Quote
Old 05-21-2018, 11:39 PM   #8
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

"Fairly tight," and "self locking." So am I hearing right that I should go back tight and not worry about the thread count or marks? Right now it's just snugged up to the thread count prior to removal. It's loose enough that I could take it back off with a 3/8 drive ratchet if I had to.

The thought that the bearing could be worn or maybe just loose crossed my mind when I removed the nut because it didn't fight the impact much at all. I have heard a slight whine at highway speed that goes away when I let off the throttle. Not sure how long it's been there because I have to listen hard to hear it.

I'm not driving the truck until I get it figured out so at least I won't be making it worse.

Thanks for the info!
BigRandy is offline   Reply With Quote
Old 05-22-2018, 11:54 AM   #9
Bigdav160
Registered User
 
Bigdav160's Avatar
 
Join Date: Apr 2011
Location: Klein Texas
Posts: 2,986
Re: Replaced pinion seal but did I do it right?

I would un-bolt the driveshaft from the yoke and see if you have any in and out play (axial). There should be zero!
__________________
My Classics:
'72 K20 Suburban + '65 Dodge Town Wagon
'72 Corvette Roadster +'67 Corvette Roadster
'73 Z-28 Camaro
'63 Ford SWB Uni Pickup
'50 Ford Coupe
Bigdav160 is online now   Reply With Quote
Old 05-22-2018, 09:53 PM   #10
ElKotze
Registered User
 
ElKotze's Avatar
 
Join Date: Nov 2014
Location: Southwest Kansas
Posts: 254
Re: Replaced pinion seal but did I do it right?

The crush sleeve is not re-usable. The correct way would be to replace the crush sleeve and pinion nut. Then tighten down until you reach the bearing pre-load of 12-14 inch-pound- that means it takes 12-14 inch-pounds to turn the yoke.
__________________
'64 C10 LWB, 283, 3speed
'68 C10 LWB, 350, 4speed
'69 C20 Custom Camper Longhorn, 350, 4speed
'72 C20 Cheyenne Super
ElKotze is offline   Reply With Quote
Old 05-22-2018, 10:15 PM   #11
Bigdav160
Registered User
 
Bigdav160's Avatar
 
Join Date: Apr 2011
Location: Klein Texas
Posts: 2,986
Re: Replaced pinion seal but did I do it right?

I'd believe that if it was spelled out in the service manual but it is not. The warranty time to replace the seal is like .5 hour. Nobody is going to completely dissemble the axle to replace a pinion seal.
__________________
My Classics:
'72 K20 Suburban + '65 Dodge Town Wagon
'72 Corvette Roadster +'67 Corvette Roadster
'73 Z-28 Camaro
'63 Ford SWB Uni Pickup
'50 Ford Coupe
Bigdav160 is online now   Reply With Quote
Old 05-22-2018, 10:28 PM   #12
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Okay. Pulled the driveshaft off and checked the nut. It was a half turn from being tight so I ran it up until I hit a hard stop the gave it a couple of hard grunts. There was no in-out play at all.

Went for a drive and there were no leaks so hopefully it's fixed. Still has a very slight whine at highway speed that goes away when I let off the gas. It had 104K miles when I got it and has 108K now. It may have had the whine when I got it but I never listened for it until now.

Do these old diffs take any special kind of 90W oil? It's an open 3.73 and I changed the old oil months ago using regular Valvoline gear oil. Not limited slip or synthetic.
BigRandy is offline   Reply With Quote
Old 05-22-2018, 11:34 PM   #13
ElKotze
Registered User
 
ElKotze's Avatar
 
Join Date: Nov 2014
Location: Southwest Kansas
Posts: 254
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by Bigdav160 View Post
I'd believe that if it was spelled out in the service manual but it is not. The warranty time to replace the seal is like .5 hour. Nobody is going to completely dissemble the axle to replace a pinion seal.
Sounds like the OP's axle should be disassembled anyway.......
Without a new crush sleeve there's no way to get the pinion bearing pre-load right. If you know what you're doing you might get it close enough to get by, I know.
__________________
'64 C10 LWB, 283, 3speed
'68 C10 LWB, 350, 4speed
'69 C20 Custom Camper Longhorn, 350, 4speed
'72 C20 Cheyenne Super
ElKotze is offline   Reply With Quote
Old 05-23-2018, 10:14 PM   #14
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by ElKotze View Post
Sounds like the OP's axle should be disassembled anyway.......
.
That's a possibility. I've never rebuilt a diff before so it may be safer in the long run to find a complete replacement and do a drop and swap. I've checked my closest wrecking yards and so far have come up empty handed.

I wouldn't mind tearing it apart if I had one to practice on first but this is the only one I've got. If I screw it up I could end up worse than when I started. From what little I know about rearends, if they are not done perfectly the whole thing is screwed

What year range would be are interchangable? I saw an 81 C-10 parked behind a house but no one answered the door.

I'm assuming not 70's-80's are 12 bolt?? Mine has a 2 pc driveshaft. I had a 77 LWB that had a 1 pc but don't remember much about the diff other than it had 3.08 gears and lasted 180,000 miles. That was a very long time ago.
BigRandy is offline   Reply With Quote
Old 05-23-2018, 11:22 PM   #15
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 21,060
Re: Replaced pinion seal but did I do it right?

What year of truck are you working on?

The truck 12 bolt was used '63-'82 on the C/K series and the truck 10 bolt '79-'86 in the C/K series and '87-'91 in the R/V series.
__________________
Power Steering Box Adapter Plates For Sale HERE
Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE
Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE
Hydroboost Mounting Plates HERE
Captainfab is offline   Reply With Quote
Old 05-24-2018, 12:07 AM   #16
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by Captainfab View Post
What year of truck are you working on?

The truck 12 bolt was used '63-'82 on the C/K series and the truck 10 bolt '79-'86 in the C/K series and '87-'91 in the R/V series.
74 long bed C10 454, TH400

I wasn't aware they went to 82. Would a 12 bolt between 63-82 be a straight swap? If so my odds may not be as bad as I thought.
Thanks!
BigRandy is offline   Reply With Quote
Old 05-24-2018, 08:00 AM   #17
Mike C
Registered User
 
Mike C's Avatar
 
Join Date: Dec 1999
Location: Austin, TX, USA
Posts: 6,528
Re: Replaced pinion seal but did I do it right?

There is no need to replace the crush sleeve when doing a seal swap. It is crushed to the correct spacer length for preload when it is assembled. Tightening it back down as tight as you can get it with a standard 1/2 ratchet will be fine. Unless it has unusual bearing wear, it will be good for years. If there is a part you should consider replacing it is the pinion nut. They lose a lot of the locking characteristics on re-use.
__________________
44 Willys MB
52 M38A1
64 Corvette Coupe
68 Camaro 'vert LT1 & TH700
69 Z/28 355 12.6's @110
69 Chevy Short Step 4 1/2"/7" drop
72 Jimmy 4WD 4spd 4" & 35's
02 GMC 2500HD 4x4 Duramax
Mike C is offline   Reply With Quote
Old 05-24-2018, 12:03 PM   #18
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by Mike C View Post
There is no need to replace the crush sleeve when doing a seal swap. It is crushed to the correct spacer length for preload when it is assembled. Tightening it back down as tight as you can get it with a standard 1/2 ratchet will be fine. Unless it has unusual bearing wear, it will be good for years. If there is a part you should consider replacing it is the pinion nut. They lose a lot of the locking characteristics on re-use.
Other than a very slight whine at highway speed it seems fine. It may be from the bearing but it's hard to say for sure. I can't feel any end play at all.

I'm hoping it lasts many more miles, but if I could find a complete diff with gears somewhere between 3.08 - 3.42 I'd like to swap it out. I don't need the 3.73s and it sucks gas like it's still 1974 when gas was $.32 a gallon. It's not terrible bad if I keep my foot out of it, but it doesn't take many squirts to drop the MPG from 10 to 7

I really appreciate the helpful info!
Randy.
BigRandy is offline   Reply With Quote
Old 05-24-2018, 11:40 PM   #19
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 21,060
Re: Replaced pinion seal but did I do it right?

A '73-'82 truck 12 bolt would be a direct bolt in into your truck. Also a '79-'87 10 bolt would be as well, but you may need a different u-joint?

Quote:
Originally Posted by BigRandy View Post
74 long bed C10 454, TH400

I wasn't aware they went to 82. Would a 12 bolt between 63-82 be a straight swap? If so my odds may not be as bad as I thought.
Thanks!
__________________
Power Steering Box Adapter Plates For Sale HERE
Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE
Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE
Hydroboost Mounting Plates HERE
Captainfab is offline   Reply With Quote
Old 05-25-2018, 12:10 AM   #20
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by Captainfab View Post
A '73-'82 truck 12 bolt would be a direct bolt in into your truck. Also a '79-'87 10 bolt would be as well, but you may need a different u-joint?
E-Brake cables too? That would be great. I don't think the rearend going to grenade anytime soon but I'd sure like an excuse to get rid of those 3.73's. I wouldn't expect any great bump in MPG but I like to run 70+ on the highway but don't want to run 3300 RPM to do it. MPG drops from 10 to about 7 when it reaches 3000.
BigRandy is offline   Reply With Quote
Old 05-30-2018, 09:32 PM   #21
YoungPup1977
Registered User
 
Join Date: Jun 2015
Location: North Carolina
Posts: 444
Re: Replaced pinion seal but did I do it right?

Qq..........

Last edited by YoungPup1977; 06-03-2018 at 07:43 AM.
YoungPup1977 is offline   Reply With Quote
Old 05-30-2018, 11:37 PM   #22
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

[QUOTE=YoungPup1977;8271793]A good used rear with 3.08 gears may help that 454 out on gas mileage, you might get an extra mile out of it....the thing about used rear ends is you really dont know if it has noise in it or any issues until you install it....than you back replacing the pinion seal and/or anything else thats bad, thats how you got here in the first place....

bearing kit = 100 bucks, 3.08 gears = 189 bucks plus you have the free forum to build this rear for ya.... how much is a used rear end that is perfect ?

This is only an opinion of mine with used stuff, I rebuild things and do not put used stuff in my vehicles......than I know what I have if I want to drive my vehicle cross country....[/QUOT

Thanks for the reply. I'm not really expecting MPG miracles with the 454 but would like to see RPM below 3K at highway speed. That's probably more of a want than a need but I do know the MPG jumps fro 8 to a whopping 10.5 if I stay around 2600.

I found a 12 bolt about 2 miles from me for $300. It's in an 81 C10 but I don't know the axle ratio. The truck has been parted out so no glove box sticker. There are no obvious leaks but you're 100% right about buying used parts - it's a dice roll.

To shift the topic a little I bought the truck last fall as a project and would normally go for new without much thought. It was a runner when I bought it but very neglected. I've taken care of the mechanical and maintenance issues and now have\had a reliable, albeit ugly, daily driver. Now my plan is on hold....

My job was eliminated after a buyout and I now spend a lot of time on the fence with some of the more costly decisions. I'm not in a bind but with no income my priorities have naturally changed. I still work on it but for now the needs outweigh the wants.

What I'd like to do is keep it running until I can resume the body work, trim, etc. Right now my conscience won't let me drop a crap load of money in it, but if it would I'd rather rebuild it myself. Never rebuilt one before but everybody starts somewhere and this forum is a living encyclopedia of knowledge.

The diff isn't shot but I'm now certain that's where that slight whine is coming from. What I don't know if it has 50 or 50,000 miles left in it.
BigRandy is offline   Reply With Quote
Old 05-31-2018, 07:17 AM   #23
YoungPup1977
Registered User
 
Join Date: Jun 2015
Location: North Carolina
Posts: 444
Re: Replaced pinion seal but did I do it right?

I guess its all about how lucky you are at dice.....I dont play dice games, I never was very lucky. Good Luck !!
YoungPup1977 is offline   Reply With Quote
Old 05-31-2018, 02:00 PM   #24
BigRandy
Registered User
 
BigRandy's Avatar
 
Join Date: Jun 2017
Location: Alexandria, Louisiana
Posts: 84
Re: Replaced pinion seal but did I do it right?

Quote:
Originally Posted by YoungPup1977 View Post
I guess its all about how lucky you are at dice.....I dont play dice games, I never was very lucky. Good Luck !!
It's nice to avoid the table and go straight to the store but I'm at a point where I have to play or leave the game, and I don't like either option.
BigRandy is offline   Reply With Quote
Old 05-31-2018, 06:51 PM   #25
YoungPup1977
Registered User
 
Join Date: Jun 2015
Location: North Carolina
Posts: 444
Re: Replaced pinion seal but did I do it right?

Qq........

Last edited by YoungPup1977; 06-03-2018 at 07:43 AM.
YoungPup1977 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 01:25 PM.


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