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 Classifieds > The 1967-1972 Chevrolet & GMC Pickups Parts Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-27-2016, 09:52 AM   #1
Custom 68
Registered User
 
Custom 68's Avatar
 
Join Date: Nov 2001
Location: Springfield, MO
Posts: 2,928
WTB rear gears

Hello all, I may be better off just purchasing new but it seems the original OEM stuff is generally better but am open to opinions.
I am looking to do a gear swap. Mine is a 12 bolt truck so I think my options are limited to either a 3.08 or 3.42. I think ideally a 3.23 (or similar) would be great but I don't believe they are available.
I figure there is a ton of the 3.08 around I want to try a good set to see what I think.
I am 5.3 turbocharged with a 4l80e.
Thanks
Dave
__________________
Dave
1968 Custom Chevy with turbo charged 5.3 gen III 4l80e swap
1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
Custom 68 is offline   Reply With Quote
Old 10-27-2016, 12:00 PM   #2
Willie Makeit
Registered User
 
Willie Makeit's Avatar
 
Join Date: Oct 2013
Location: Alabama
Posts: 1,210
Re: WTB rear gears

I've got a set of NOS GM 3.73 gears that I'd be willing to part with. PM if interested.

P.S. 3.42 was never offered in the GM truck 12 bolt. 3.08 - 3.73 - 4.11
Willie Makeit is offline   Reply With Quote
Old 10-27-2016, 12:01 PM   #3
Willie Makeit
Registered User
 
Willie Makeit's Avatar
 
Join Date: Oct 2013
Location: Alabama
Posts: 1,210
Re: WTB rear gears

P.S. I'm running 3.73 gears behind a supercharged 5.3 & 4L80E and with a 30" tall tire it's just about perfect for low end grunt in gears 1-2 and highway cruising once OD kicks in.
Willie Makeit is offline   Reply With Quote
Old 10-27-2016, 12:31 PM   #4
Custom 68
Registered User
 
Custom 68's Avatar
 
Join Date: Nov 2001
Location: Springfield, MO
Posts: 2,928
Re: WTB rear gears

Thanks Willie, first off I currently have set of 3.73 (aftermarket) and have a set of 4.11 installed and that proved to be just too low (numerically high) and was afraid going to 3.73 would be too small of a jump. I like to drive this on the highway and my last trip was a little tough running at speed for 1300 miles with the current gearing. It was setup when I had the double overdrive of the T56.
I believe I had found a set of aftermarket 3.42 made to fit but had not confirmed. I didn't think any was offered by GM but was not sure.
on to you second post, it sounds like you are happy with the 3.73 gearing. My tires are about 3/4 inch shorter than yours so they are very close. My turbo is not very big so it is on the verge of boost when I am running down the highway. I dont know how different the supercharging is over the turbo setup. I have just heard and read the turbos like the added load produced by the higher gearing. I know currently I can blow thru the first 2 gears really quick with the 4.11.
Thanks
Dave
__________________
Dave
1968 Custom Chevy with turbo charged 5.3 gen III 4l80e swap
1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
Custom 68 is offline   Reply With Quote
Old 11-01-2016, 06:47 PM   #5
builtnb
Active Member
 
Join Date: Feb 2012
Location: Ilion, NY
Posts: 130
Re: WTB rear gears

I have a nice set of 3.08 gears, if you are still looking. I can do $75 shipped. wayne
builtnb is offline   Reply With Quote
Old 11-01-2016, 08:38 PM   #6
Custom 68
Registered User
 
Custom 68's Avatar
 
Join Date: Nov 2001
Location: Springfield, MO
Posts: 2,928
Re: WTB rear gears

Thanks Wayne I just went and checked and unfortunately I purchased the carrier for my factory 3.73 sooooo I can't use the higher (lower numerical) than the 3.73. I need to regroup and decide what I want to do
__________________
Dave
1968 Custom Chevy with turbo charged 5.3 gen III 4l80e swap
1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
Custom 68 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 09:27 AM.


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