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 08-10-2011, 10:46 PM   #1
Project77
Registered User
 
Join Date: Dec 2010
Location: Hallettsville, Texas
Posts: 363
what kind of rear end do i have?

i dont know much about them i went out today cleaned it off got some numbers and this is what i got drivers side of front of differential 3896839 and passenger side of rear differential gm75 and on top of the passenger long tube there where three letters kdu its a 12 bolt rear end on a 77 chevy long wheel base i believe its stock but im not to sure if any more information is needed let me know ill go back out tmoro and see what else i can dig up
Project77 is offline   Reply With Quote
Old 08-11-2011, 12:44 AM   #2
Redcap
Registered User
 
Join Date: May 2010
Location: Lewis County, WA
Posts: 1,523
Re: what kind of rear end do i have?

It is a 12 bolt.
Redcap is offline   Reply With Quote
Old 08-11-2011, 12:50 AM   #3
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 23,246
Re: what kind of rear end do i have?

What info are you looking for other than it is a 12 bolt? If you are wanting to know gear ratio and weather it is a posi or not, I would just pull the rear cover and have a look. More than likely the gear oil could stand to be changed. The differentials are possibly the most neglected when it comes to maintainence.
__________________
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 08-11-2011, 01:50 AM   #4
Redcap
Registered User
 
Join Date: May 2010
Location: Lewis County, WA
Posts: 1,523
Re: what kind of rear end do i have?

Quote:
Originally Posted by Captainfab View Post
What info are you looking for other than it is a 12 bolt? If you are wanting to know gear ratio and weather it is a posi or not, I would just pull the rear cover and have a look. More than likely the gear oil could stand to be changed. The differentials are possibly the most neglected when it comes to maintainence.
Pretty much. This isn't like the Dana axles and their BOM numbers. Pull the covers and take a look!
Redcap is offline   Reply With Quote
Old 08-11-2011, 01:26 PM   #5
Project77
Registered User
 
Join Date: Dec 2010
Location: Hallettsville, Texas
Posts: 363
Re: what kind of rear end do i have?

im afraid of what im going to find and what do i do when i pull the cover? how do i find out what gearing there is? and how will i properly seal it back up?
Project77 is offline   Reply With Quote
Old 08-11-2011, 01:28 PM   #6
Project77
Registered User
 
Join Date: Dec 2010
Location: Hallettsville, Texas
Posts: 363
Re: what kind of rear end do i have?

and the reason for it being the most neglected is because nobody really knows much about them
Project77 is offline   Reply With Quote
Old 08-11-2011, 02:22 PM   #7
ka_jd7and1
is a fungineer
 
ka_jd7and1's Avatar
 
Join Date: Jan 2009
Location: Bakersfield, CA
Posts: 795
Re: what kind of rear end do i have?

The ring gear will have some numbers stamped on it, two of those numbers will tell you what ratio you have (the numbers how many teeth the ring gear and pinion gear have). You will have to divide the big number by the little number. For example, my truck has 41 11 on the ring gear, which 41/11 = 3.73 ratio.

I use silicone on my rear end covers, I don't use a gasket. Some people may disagree on the right or best way to do it.
__________________

2003 S10, 2.2 auto- the daily driver, currently with a 2"/2" drop and some minor engine bolt-ons

1978 Impala 2-door, race 350/T350 - the new race car, in progress

1968 Chevy C10 longbed- 3/5 drop, currently undergoing a heart transplant
ka_jd7and1 is offline   Reply With Quote
Old 08-11-2011, 03:48 PM   #8
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

"what kind of rear end do i have?"


Quote:
Originally Posted by Project77 View Post
i dont know much about them........ill go back out tmoro and see what else i can dig up
Quote:
Originally Posted by Redcap View Post
It is a 12
Quote:
Originally Posted by Captainfab View Post
What info are you looking for? More than likely the oil could stand to be changed. ...possibly the most neglected when it comes to maintainence.
Quote:
Originally Posted by Redcap View Post
Pull the covers and take a look!
Quote:
Originally Posted by Project77 View Post
im afraid of what im going to find...... and how will i properly seal it back up?
Quote:
Originally Posted by Project77 View Post
and the reason for it being the most neglected is because nobody really knows much about them
Quote:
Originally Posted by ka_jd7and1 View Post
The ring will have some numbers stamped on it.......I use silicone on my rear......I don't use a gasket. Some people may disagree on the right or best way to do it.


LMFAO.....I didn't realize it could be so much fun to only slightly "quote" someone in the reply. Imagine if someone outside the board read this??? Man.....I'm in a weird mood today!!!
prostreetC-10 is offline   Reply With Quote
Old 08-11-2011, 07:56 PM   #9
LONGHAIR
just can't cover up my redneck
 
Join Date: May 2004
Location: Columbus OH
Posts: 11,414
Re: what kind of rear end do i have?

Quote:
Originally Posted by prostreetC-10 View Post
Man.....I'm in a weird mood today!!!
OK, back in your cage.....who let you out anyway?
__________________
You can review the site's rules here.



Quote:
Originally Posted by Longhorn Man View Post
As for reading directions...
The directions are nothing but another man's opinion.
Learn from the mistakes of others, you won't live long enough to make them all yourself...

Bad planning on your part does not necessarily constitute an instant emergency on my part....

The great thing about being a pessimist is that you are either pleasantly surprised or right.
LONGHAIR is offline   Reply With Quote
Old 08-11-2011, 09:10 PM   #10
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

"I don't care who you are.......that's funny right there!"
prostreetC-10 is offline   Reply With Quote
Old 08-11-2011, 10:57 PM   #11
usmcchevy
Has more rust than truck...
 
usmcchevy's Avatar
 
Join Date: Apr 2005
Location: Ivanhoe, MN
Posts: 2,421
Re: what kind of rear end do i have?

Quote:
Originally Posted by LONGHAIR View Post
OK, back in your cage.....who let you out anyway?
__________________
1972 Custom/10 SWB, 4.8/4l80e
Build thread

LSx Swap FAQ index
usmcchevy is offline   Reply With Quote
Old 08-12-2011, 12:18 AM   #12
Project77
Registered User
 
Join Date: Dec 2010
Location: Hallettsville, Texas
Posts: 363
Re: what kind of rear end do i have?

please dont turn my thread into a joke im a very commited 16 year old trying to learn everything possible this is my daily driver to work and all around its all i got and im taking all neccisary precautions in working on it and figuring everything i can about it i want to learn and not be critized about it so please if you could stop thank you
Project77 is offline   Reply With Quote
Old 08-12-2011, 01:42 AM   #13
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

Quote:
Originally Posted by Project77 View Post
i want to learn and not be critized about it so please if you could stop thank you

Man.....wasn't trying to critize you and I'm not sure how you took it that way. Not sure why that struck me as so funny when I was reading all the replies after reading the thread title. I was just in a goofy mood. We are just a bunch of guys and a few gals hanging out helping each other and having fun along the way. It's going to happen from time to time. It's awesome that you are only 16 and getting into all this. This board is a wealth of information for you to tap into. Just try and have a little fun along the way.

My apologies if I disrupted the flow of the thread.
prostreetC-10 is offline   Reply With Quote
Old 08-12-2011, 01:50 AM   #14
fastwillie 696969
~Rest In Peace~
 
fastwillie 696969's Avatar
 
Join Date: May 2005
Location: CALIFORNIA NOR CAL
Posts: 9,707
Re: what kind of rear end do i have?

i thought it was going to be one of those the wife ask Question
__________________
is it fast ? it has a lighting bolt donut?


B___H please, I can remove 90% of your so called "beauty" with a kleenex
fastwillie 696969 is offline   Reply With Quote
Old 08-12-2011, 11:00 AM   #15
stich626
Account Suspended
 
Join Date: Sep 2010
Location: hingham ma
Posts: 1,721
Re: what kind of rear end do i have?

pull the cover... can't hurt,, but before you do.. on the pass side of the rear center case there is a plug (fill plug) it's between the 2 webs, make sure you can get this out before you pull the cover.. (i used a rathet witha 3" extention where you'd normally put a socket on the extention goes in the plug to turn it.. get it to turn then move on..
before you do, go to parts store and get a 12 bolt gasket(some don't use a gasket and use just rtv) I've had the best luck with a gasket and a light coat of rtv on both sides..
and get gear oil..(2 quarts/two bottles) and because you didn't know yet if it's a posi. get the gear oil thats got the posi additive in it..(it'll say it on the bottle)
pull the cover, write down the numbers, and take a pic of the diff. if the center has springs and plates, it's a posi.. if not it's an open..
I spray brake clean in there to get all the junk off the floor of the case, then use rags..
clean the face of the rear end where the cover bolts to.. the old gasket will be a p.i.t.a. to remove it all. you must get it all off.. same with the cover, take your time..
look at the cover, at the bolt holes if the hole isn't flat, light taps of a hammer to flatt'n it.. (if the covers never been off, this is not needed 98% of the time)..
reseal the cover (your choice rtv by itself or a gasket)
snug up the bolts, then in a chris cross pattern tight'n them.. forget the torque spec. (someone will chime in) I've been doing this for years and use "feel" for when enough
just don't crank them down..
now fill it.. I find a piece of rubber hose works great to get the oil into the rear..
I use an old piece of plumping as I had 1/2 copper around with an elbow.. but for most the rubber hose is all you need, most don't do it as much as me either..
while under there, check the vent hose,,
check for leaks, and your done,, recheck for leaks in a few days, then in a week. retorque bolts as needed..
stich626 is offline   Reply With Quote
Old 08-12-2011, 11:11 AM   #16
stich626
Account Suspended
 
Join Date: Sep 2010
Location: hingham ma
Posts: 1,721
Re: what kind of rear end do i have?





stich626 is offline   Reply With Quote
Old 08-12-2011, 11:12 AM   #17
stich626
Account Suspended
 
Join Date: Sep 2010
Location: hingham ma
Posts: 1,721
Re: what kind of rear end do i have?

here is the fill plug local
Attached Images
 
stich626 is offline   Reply With Quote
Old 08-12-2011, 11:18 AM   #18
stich626
Account Suspended
 
Join Date: Sep 2010
Location: hingham ma
Posts: 1,721
Re: what kind of rear end do i have?

now would be a great time to get a note book (back to school sales) 5 subject is best(engine/chassis/body/elictrical/drivetrain)
and write down the info as you go.. like here, the gear part # and ratio, posi or not, date and miles of new gasket, and lube,, lube used, this will be a big help down the line and if you ever sell it. a big plus..
stich626 is offline   Reply With Quote
Old 08-12-2011, 02:40 PM   #19
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

THere we go.....back on track. Thanks Stich!
prostreetC-10 is offline   Reply With Quote
Old 08-12-2011, 11:41 PM   #20
Project77
Registered User
 
Join Date: Dec 2010
Location: Hallettsville, Texas
Posts: 363
Re: what kind of rear end do i have?

thank you for filling me in on all of the info very much appreciated when i get some time in my hesty schedual (and yes im a very busy 16 year old got lots on the to do list) ill get to it right away and sorry for misunderstanding your playing around just been really kind of stressed lately seeing things differently than opossed thank you guys
Project77 is offline   Reply With Quote
Old 08-12-2011, 11:52 PM   #21
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

We cool!
prostreetC-10 is offline   Reply With Quote
Old 08-13-2011, 01:17 PM   #22
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,921
Re: what kind of rear end do i have?

A little ribbin' is good now and again. Makes ya laugh... and a little laughter is good for ya!

Keep pluggin' away... I will offer this though. A lot of questions that get asked are usually pretty common knowledge. Stuff that is usually available in a good repair/service manual, or with a simple Google search. I do understand that not every person has the same knowledge base. I've been wrenchin' on cars and trucks for 30+ years. I learn new stuff all the time. I've learned a lot more about engines and transmissions here in the last few years than I thought I already knew.

Good group of guys here. But ya gotta watch that kid from Holleyville Oregon... he's a character. He'll grow on ya though.

Gary

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 08-13-2011, 01:26 PM   #23
prostreetC-10
My Carbon Footprint
 
prostreetC-10's Avatar
 
Join Date: Oct 2008
Location: Orygun
Posts: 5,527
Re: what kind of rear end do i have?

Glad to know that 43 is considered a kid. You outta see me drive on the back roads. You'd swear I'm 19 again!

FYI.....Gary is the only guy in Washington that actually knows how to drive!
prostreetC-10 is offline   Reply With Quote
Old 08-13-2011, 01:30 PM   #24
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,921
Re: what kind of rear end do i have?

HAHA! I'm a 43 year old kid too!

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 08-13-2011, 01:42 PM   #25
J Knight
Registered User
 
J Knight's Avatar
 
Join Date: Jun 2011
Location: Baytown TX
Posts: 2,219
Re: what kind of rear end do i have?

I think this whole thread was informatively entertaining!
__________________
John
82 Chevy Silverado 350ci/TH350
J Knight 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 08:20 PM.


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