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 01-13-2015, 09:23 PM   #1
Bobby277
Registered User
 
Bobby277's Avatar
 
Join Date: Aug 2014
Location: Kansas
Posts: 37
Talking 78 C10 Rear End Help

Hello all, I am in need of some knowledge!

A buddy of mine has a short bed 78 c10, it is what some might call a one wheel wonder lol

Can any of you give me any more information on the rear end in this truck?
Are there any Posi units or lockers compatible?

It has seen better days but still has good bones, so we were throwing around the idea of taking it off the road and turning it into a drag truck of sorts.

If any of you have experience building these trucks to drag I wouldn't mind hearing anything you had to say about that either, but my primary questions are about the rear.

Thanks!
__________________
1989 Isuzu Trooper - 230000 miles

1968 c20 - 292 straight six - fourth owner - 96000

1978 400ci small block PROJECT
Bobby277 is offline   Reply With Quote
Old 01-13-2015, 09:57 PM   #2
cableguy0
Senior Member
 
Join Date: Apr 2000
Location: Delta,Pa
Posts: 14,948
Re: 78 C10 Rear End Help

The rear should be a 12 bolt truck rear. Cant tell you gear ratio but that's easy to figure out on your own. Just pull the cover and either count the teeth on the ring and pinion then divide or look for the stamp on the ring gear. There are plenty of options for posis and lockers. I prefer an eaton clutch type posi especially on anything street driven. Lockers can be rough on the street.

Plenty of these trucks being drag raced. The leaf springs in back leave a lot to be desired when it comes to traction. Cal trac bars can do wonders though.
__________________
Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.
cableguy0 is offline   Reply With Quote
Old 01-13-2015, 11:08 PM   #3
cadillac_al
Registered User
 
Join Date: Oct 2013
Location: Maine
Posts: 2,376
Re: 78 C10 Rear End Help

If you are just going to thrash it and drag it then all you need is a Lincoln locker (welded).
I'm sure there are lots of how to articles and videos out there showing how it's done.
__________________
76 Chevy K20
76 GMC K15
77 Chevy C10
77 Chevy K10
cadillac_al is offline   Reply With Quote
Old 01-13-2015, 11:41 PM   #4
Bobby277
Registered User
 
Bobby277's Avatar
 
Join Date: Aug 2014
Location: Kansas
Posts: 37
Re: 78 C10 Rear End Help

Good info! And do those Lincoln lockers really hold up??
__________________
1989 Isuzu Trooper - 230000 miles

1968 c20 - 292 straight six - fourth owner - 96000

1978 400ci small block PROJECT
Bobby277 is offline   Reply With Quote
Old 01-14-2015, 01:01 AM   #5
Captainfab
60-66 Nut

 
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 23,252
Re: 78 C10 Rear End Help

I would go with a spool or mini spool before I would do a 'Lincoln Locker' (welding the spider gears). When those come apart it isn't pretty. And you can be assured it will come apart sooner or later.

An Eaton clutch style posi would be best for a street/strip truck, or a Detroit locker for a mainly strip with a little street truck. Or if strictly strip a spool as I mentioned above.
__________________
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 01-14-2015, 08:51 AM   #6
Bobby277
Registered User
 
Bobby277's Avatar
 
Join Date: Aug 2014
Location: Kansas
Posts: 37
Re: 78 C10 Rear End Help

Do you think I could find a salvageable posi unit In a junkyard somewhere? A locker would be better I think but I am not sure if I could find one of those in a junkyard.

What type of truck would I be looking for that could have this?

Thanks
__________________
1989 Isuzu Trooper - 230000 miles

1968 c20 - 292 straight six - fourth owner - 96000

1978 400ci small block PROJECT
Bobby277 is offline   Reply With Quote
Old 01-14-2015, 07:07 PM   #7
cableguy0
Senior Member
 
Join Date: Apr 2000
Location: Delta,Pa
Posts: 14,948
Re: 78 C10 Rear End Help

Quote:
Originally Posted by Bobby277 View Post
Do you think I could find a salvageable posi unit In a junkyard somewhere? A locker would be better I think but I am not sure if I could find one of those in a junkyard.

What type of truck would I be looking for that could have this?

Thanks
It will be a wild goose chase. Most of the 12 bolts didn't have a posi factory in trucks. The trucks from I think 80 and up all had 10 bolt rears and the posi in them is not compatible with the 12 bolt and its also a turd. They are known as gov-bombs. Proper name is a gov lock but they tend to explode fairly easily especially when you thrash them. Your probably going to be stuck buying a new unit.
__________________
Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.
cableguy0 is offline   Reply With Quote
Reply

Bookmarks

Tags
drag truck, locker, posi, rear end setup


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 11:53 AM.


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