I was wondering if anybody can help me with a possible ratio in my '80 El Camino. I originally had a 229 ci v-6 with a TH-200C which is the smaller 3 speed tranny. I was wondering if anyone was pretty knowlegeable in this area with what the early 5th gens came with. Mainly the only reason why I am asking is because its a lot easier than popping off the rear dif cover and counting the teeth on the ring and pinion. I was also thinking about changing it out and could use some suggestions on a new set of rear gears. I have a 350-350 setup now and the car sees a lot of highway miles right now but the ratio I have now seems to be too low for my stall converter (2500) and the cam I run calls for it but the fluid and tranny seem to get a little hotter than normal even with a tranny cooler. Any suggestions??
Thanxs
-Yoshi

Just wondering. Did you do the swap (engine) yourself? I have an 81 with the V6 and will be swapping in a V8 starting next month. Never did it before, wondering what problems I'll run into.
My boss told me to mark the drive shaft and the rear wheel.
Get someone to watch the drive shaft and count the rotations and number of revolutions of the wheel. This should give you your ratio (roughly).

I was wondering if anyone was pretty knowlegeable in this area with what the early 5th gens came with.

Crawl under the rear end with a wire brush and a flashlight. On the front of the passenger side axle tube there will be a code of around seven or eight letters and numbers. (Example 2TH 287 A) Post the code here and we'll decipher it for you. IIRC, Most of the early 5th generation Elkys came with either a 2.41, 2.73, or 3.08 rear gears.

:mrgreen:

Ernie thanx for that info, I didn't even know there were casting numbers around there. I will get you the numbers in a few days, its about time to change my oil here pretty soon anyway. Thanx for the info again.
-Yoshi

Ernie thanx for that info, I didn't even know there were casting numbers around there.

Actually it's not cast, it's stamped. Use the wire brush very liberally.

:mrgreen:

Oops. Stamped does make more sense since axle tubes aren't cast. My bad
-yoshi

IIRC, Most of the early 5th generation Elkys came with either a 2.41, 2.73, or 3.08 rear gears.

:oops: Oops...I missed one...the 2.56

OK...here is the complete list of standard El Camino rear ends for 1980:

All States except California
3.8 Liter (LC3) w/3sp manual (MM3) - 2.73:1
3.8 Liter (LC3) w/automatic ( MX1) - 2.73:1
4.4 Liter (L39) w/automatic ( MX1) - 2.56:1
5.0 Liter (LG4) w/automatic ( MX1) - 2.41:1
5.0 Liter (LG4) w/4sp manual (MM4) - 3.08:1

California only
3.8 Liter (LC3) w/automatic ( MX1) - 2.73:1
5.0 Liter (LG4) w/automatic ( MX1) - 2.41:1

Limited Slip Differential (Posi) was available for all axle ratios.

Interesting footnote: You couldn't get a 3 or 4 speed manual trasmission in California.

Hmmmmm... :?:

:mrgreen:

Wasn't 3.73 available too on the Black/Royal Night and SS?

Wasn't 3.73 available too on the Black/Royal Night and SS?

There were no 5th generation El Camino that were offered with a 3.73 rear end. The 3.08 was the highest you could get.

:mrgreen:

Digity I just finished the swap you want on an 81, mine was a v-6 run on lpg. the swap is easy the major thing is to remember to relocate your motor mounts on the frame the holes are there. for a v-8 you have to move them to the back holes. my only other problem has been marrying new with old. i put a 700r behind my sb400 and hooking up the tv cable with the factory accelerater cable, nothing in the way of brackets seem to fit finally found an adjustable bracket at auto zone of all places. also found out TCI has a bracket and an extra long adjustable tv cable. the only other thing is your xmsn mount on the crossmember has to be cut back some and hole redrilled to clear the xmsn pan and use your mount from the V-6 xmsn.

Can anybody help me figure out what ratio the differential has in my 84 El Camino? The glove box sticker is gone, along with the build sheet. I bought it from the original 85 year old owner....clueless. The code, stamped in the right front of the rear axle is 6AV CO96. Thanks!

The code, stamped in the right front of the rear axle is 6AV CO96.
AV is a 3.08 non-posi made in Buffalo, NY

The Book I have is showing a3.23 and 3.42 option for the `82 yr.. My book shows that my AX code is 2.73 posi, does that sound right.

Thank You

The Book I have is showing a3.23 and 3.42 option for the `82 yr.. My book shows that my AX code is 2.73 posi, does that sound right.
Your book is wrong on both counts. There was no 3.23 or 3.42 rear end offered in any 5th gen. The AX code is a 2.73 non-posi, BX would be a 2.73 posi. What is the name of that book?

The Book I have is showing a3.23 and 3.42 option for the `82 yr.. My book shows that my AX code is 2.73 posi, does that sound right.
Your book is wrong on both counts. There was no 3.23 or 3.42 rear end offered in any 5th gen. The AX code is a 2.73 non-posi, BX would be a 2.73 posi. What is the name of that book?
I pulled my head out of the dark spot and Mine is actually CX!

Thanks

So a 1983 Chevy El Camino Conquista .... had a 305 and a 350 turbo tranny ....so 2:41?

So a 1983 Chevy El Camino Conquista .... had a 305 and a 350 turbo tranny ....so 2:41?


That would depend on the Code Stamped on your Housing
Crawl under the car, (use jack stands, to be safe) on the passenger side, on the front of the Axle Tube, use a wire brush, clean the Tube. There you will find a stamped code, two letters, then go to this link ↓↓ and look it up for your year. It's that easy.
http://elcaminocentral.com/showthread.php?t=27935&highlight=gear+ratio (http://elcaminocentral.com/showthread.php?t=27935&highlight=gear+ratio)

8ax (either c or g) 055 (either i or 1), which it this? sorry I cant help out more than that.

2.73..... 7.5"....... AB, BB, AX, BX, RX

:secret:

ok, according to my build sheet I have the:

GU1 2.41 RATIO AX

Question is...does the "AX" stand for Axel, or is that the code. And without crawling underneath the car (it's getting too cold for that) would that "AX" mean I have posi or non-posi?