Rear Axle Ratio Charts For 1967 - 1972 GM Trucks

[62k10&84k20burb]

Ok, according to this, 1967 c20 duallys do exist?

[FreeRangeChicken]

Here's another resource for differential (and engine, and VIN) codes.

http://www.gmcpauls.com/67-72_chevy.htm

[Jake1971]

Subscribed, good info here

[chuckmc8]

Thanks for posting this Leon. I need this info from time to time and always had to look for it. Is there a 1971 page like the 1972 chart in post #2? I just need the 5 lug stuff....

[LockDoc]

Originally Posted by chuckmc8

Thanks for posting this Leon. I need this info from time to time and always had to look for it. Is there a 1971 page like the 1972 chart in post #2? I just need the 5 lug stuff....

The '71 chart is at the bottom of post #1. Is that what you need?

LockDoc

[chuckmc8]

"The '71 chart is at the bottom of post #1. Is that what you need?"

Yes, that's it and I just missed it. Thanks!

[Elefuntman]

Is there any other places to look for the codes? I have a 69 C10, on the passenger side axle tube: "R V 0630 W2", and under that an "E", I do not see any code like it, does anyone know what ratio it is? Thanks

[LockDoc]

Originally Posted by Elefuntman

Is there any other places to look for the codes? I have a 69 C10, on the passenger side axle tube: "R V 0630 W2", and under that an "E", I do not see any code like it, does anyone know what ratio it is? Thanks

Did you look in the location pictured in post #19?

LockDoc

[Elefuntman]

I will try there, from reading the posts I thought you guys were talking about a "K" series Dana. Thanks!

[dbelanger24]

Originally Posted by LockDoc

-
Usually on the passengers side axle tube.

LockDoc

so judging by what you've posted for a picture the TDE would stand for 3.07:1 gears ina C10? What would the 11 and 13 stand for?

[LockDoc]

Originally Posted by dbelanger24

so judging by what you've posted for a picture the TDE would stand for 3.07:1 gears ina C10? What would the 11 and 13 stand for?

That would be correct. I think that may be a date code ie: 11th month, 13th day but I don't know for sure.

LockDoc

[VWNate1]

Dave ;

Never fear any flaming here ! .

The good folks here collectively know _everything_ and are always willing to share , no question is foolish no matter how mundane you think it is .

O.K. ? .

Seriously , i worked on these trucks when new , later i was a Dealer Mechanic and I have learned more here than all those years of hands on working so ASK AWAY ! .

[88Stanger]

thank you!!!

[LockDoc]

Originally Posted by 88Stanger

thank you!!!

No problem, glad folks are getting some use out of the info....

LockDoc

[chefk85]

Great post! lots of good info here. the trouble I'm having is I cannot find my code! it reads as follows and I am not mistaken. TAY W175 2. will post pics if it becomes necessary but theres a good chance I'm missing it somewhere amongst all the darn codes. Any ideas?

thanks in advance,
chefk85

[chefk85]

here is a pic(if I loaded it right) of the code TAY W175 2 pass. side near the top by brake tee.

[LockDoc]

Originally Posted by chefk85

here is a pic(if I loaded it right) of the code TAY W175 2 pass. side near the top by brake tee.

Always a chance one was omitted in the charts or a housing got stamped wrong. If you take the cover off please post up the numbers on the ring gear so there is a record of it in the thread.

Thanks,
LockDoc

[chefk85]

You know I found a thread where a guy had the same thing going on. His was a 3.07 non posi. My front end is 3.07 so I assume I've got the same. If I take the cover off I will be sure to post pics.

Thanks again,
Chefk85

[mkmc69]

Good information!

[the idiocracy]

I don't know what the C14 is about, but I just looked at my 1967 C10 pickup and there is an HA stamped clear as day on the top side of the passenger tube, pretty close the the pumpkin.

3.73. Super. I was really expecting to see something like a 5.10 or higher based on the fact that I am at 3000 rpms at 65mph.

I see a 3.23 rear gear in my future. Anyone know what diameter the ring gear is? I want to say 8.5", but I also know that GM did an 8.625" ring gear as well. Anyone know?

[LockDoc]

Originally Posted by the idiocracy

I don't know what the C14 is about, but I just looked at my 1967 C10 pickup and there is an HA stamped clear as day on the top side of the passenger tube, pretty close the the pumpkin.

3.73. Super. I was really expecting to see something like a 5.10 or higher based on the fact that I am at 3000 rpms at 65mph.

I see a 3.23 rear gear in my future. Anyone know what diameter the ring gear is? I want to say 8.5", but I also know that GM did an 8.625" ring gear as well. Anyone know?

I always just figured the C14 was a misprint but I can't prove that one way or the other....

LockDoc

[fist5366]

So is this out of a 70 with posi I was told it was out of a blazer with 3.73 gears. It was in the truck when I got it if I remember right we pulled and checked gears but that was 20 yrs ago . I'm sure they could have been changed at some point

[LockDoc]

Originally Posted by fist5366

So is this out of a 70 with posi I was told it was out of a blazer with 3.73 gears. It was in the truck when I got it if I remember right we pulled and checked gears but that was 20 yrs ago . I'm sure they could have been changed at some point

TPR..... It shows that code for a '70 KE-10, 3.07:1 ratio and a '71 G-10, 3.36:1 ratio.

Yep, in 40+ years anything is possible.

LockDoc

[garyd1961]

Thanks for posting this but I have a question. My axle code is TDE which just shows 3.07 gears. I thought my rear TDE was posi traction. The rear is not in the truck but if I lock one axle and the yoke in place the other axle will not turn. I thought this meant posi traction.

[fist5366]

Thanks this is all great info