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 07-19-2011, 08:33 AM   #1
ubtripn
Registered User
 
ubtripn's Avatar
 
Join Date: Apr 2010
Location: Boise, ID
Posts: 1,280
Synthetic or Regular Differential Oil

Is it ok to put Synthetic in my differential after it has been running fossel based, regular oil for so may years? I heard it will looseen seals, cause leaks, etc.. if you switch midway through with any engine.
ubtripn is offline   Reply With Quote
Old 07-19-2011, 09:25 AM   #2
70cst
Senior Member
 
70cst's Avatar
 
Join Date: Feb 2001
Location: New Madison, Ohio
Posts: 21,373
Re: Synthetic or Regular Differential Oil

Some reading for you ...

fluids/oils/gear lube
http://67-72chevytrucks.com/vboard/s...d.php?t=177957

someone please tell me this guy is full of BS
http://67-72chevytrucks.com/vboard/s...d.php?t=378304
__________________
A husband can be right...or...A husband can be happy.

67-72 Chevy and GMC Trucks...The Classic Truck for the Classic Folk.

1970 CST Two tone green, 402BB, 400 Automatic, Tach, Buckets, AC, AM-FM, Tilt, GM CB, GM 8 Tract, LWB, etc

JOHN 17:3...The better side of "LIFE"


Remember: Everyday is a good day...Some are just gooder!
70cst is offline   Reply With Quote
Old 07-19-2011, 09:26 AM   #3
ubtripn
Registered User
 
ubtripn's Avatar
 
Join Date: Apr 2010
Location: Boise, ID
Posts: 1,280
Re: Synthetic or Regular Differential Oil

Thanks
ubtripn is offline   Reply With Quote
Old 07-19-2011, 09:30 AM   #4
70cst
Senior Member
 
70cst's Avatar
 
Join Date: Feb 2001
Location: New Madison, Ohio
Posts: 21,373
Re: Synthetic or Regular Differential Oil

Quote:
Originally Posted by ubtripn View Post
Thanks
Glad to help. I try and do one good deed a month
__________________
A husband can be right...or...A husband can be happy.

67-72 Chevy and GMC Trucks...The Classic Truck for the Classic Folk.

1970 CST Two tone green, 402BB, 400 Automatic, Tach, Buckets, AC, AM-FM, Tilt, GM CB, GM 8 Tract, LWB, etc

JOHN 17:3...The better side of "LIFE"


Remember: Everyday is a good day...Some are just gooder!
70cst is offline   Reply With Quote
Old 07-19-2011, 09:42 AM   #5
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,690
Re: Synthetic or Regular Differential Oil

synthetc oil is the best thing you can do for your diff.
Longhorn Man is offline   Reply With Quote
Old 07-19-2011, 09:56 AM   #6
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: Synthetic or Regular Differential Oil

i use synthetic lubrication in everything motor tranny rearend and also wheel bearings// have had noticable increase in milage and slightly more performance in my real world test uses

the last two new GM vehicles i got came with synthetic right from the GMfactory//2004silverado and 2008 HHRss
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 07-19-2011, 10:13 AM   #7
Stocker
20' Daredevil (Ret)
 
Stocker's Avatar
 
Join Date: May 2003
Location: Jefferson State
Posts: 13,722
Re: Synthetic or Regular Differential Oil

Quote:
Originally Posted by ubtripn View Post
Is it ok to put Synthetic in my differential after it has been running fossel based, regular oil for so may years? I heard it will looseen seals, cause leaks, etc..
My K20 had dino in the diffs (& t-case) for close to three decades before I changed to synthetic. No problems....
__________________
- Mike -

1972 K20 LWB 350/350/205

RIP El Jay
Stocker is offline   Reply With Quote
Old 07-21-2011, 03:12 PM   #8
ubtripn
Registered User
 
ubtripn's Avatar
 
Join Date: Apr 2010
Location: Boise, ID
Posts: 1,280
Re: Synthetic or Regular Differential Oil

Right on, synthetic it is. Thanks!
ubtripn is offline   Reply With Quote
Old 07-21-2011, 03:31 PM   #9
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,971
Re: Synthetic or Regular Differential Oil

Unless it has a positraction rearend. Some Synth oils aren't compatible with a positraction diff. Or the other way around...

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 07-21-2011, 03:35 PM   #10
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: Synthetic or Regular Differential Oil

Quote:
Originally Posted by GASoline71 View Post
Unless it has a positraction rearend. Some Synth oils aren't compatible with a positraction diff. Or the other way around...

Gary
most all synthetic i know of is no problem in posi rears in fact most you dont even need a posi additive like you do with dinogrease
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 07-21-2011, 08:16 PM   #11
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,690
Re: Synthetic or Regular Differential Oil

yeah... I've never heard of that one. Sounds like yet another one of the millions of myths about synthetic oils.
Longhorn Man is offline   Reply With Quote
Old 07-21-2011, 09:27 PM   #12
oldblue1968chevy
Grandpa in the rustmobile...
 
oldblue1968chevy's Avatar
 
Join Date: Nov 2008
Location: Spokane WA/Viola TN
Posts: 11,422
Re: Synthetic or Regular Differential Oil

great my parts guy told me synthetic is a fluke and i put dino in my diff lol
__________________
John

Goose-1968 C10 355,9.32-1CR, Vortec Heads ,262 voodoo, 3.73:1 3OTT (HS ride/beater/farm truck)
http://67-72chevytrucks.com/vboard/s...d.php?t=317684

Grams 53-1953 Chevrolet Belair
http://67-72chevytrucks.com/vboard/s...=1#post4327784

1969 Chevy C10 Shortbed 4.5/6?" Frame off resto
http://67-72chevytrucks.com/vboard/s...d.php?t=548136

1999 Toyota Tacoma 4x4
oldblue1968chevy is offline   Reply With Quote
Old 07-21-2011, 10:50 PM   #13
chevytruckluver
Eat, Sleep, Drive a Chevy
 
chevytruckluver's Avatar
 
Join Date: Apr 2010
Location: the town of the cow, Texas
Posts: 1,152
Re: Synthetic or Regular Differential Oil

I am running Redline Heavy Shockproof in my rear, its a posi and did not do the additve as directed by the shop that built the rear. The owner told me he tested diffrent brands at the track and the Redline proved to run cooler thus working better to reduce friction
__________________
Trey
Silence may be Golden, but Duct Tape is Silver!

72 Short Step
57 "big window" short step
chevytruckluver 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 10:06 PM.


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