Ok so I've seen it a hundred times. Automatics are 36's,
sticks are 44's.
Every time I call someone about buying gears, they try to tell me
I've got a DANA 36.
My car's a stick.
I look on the bottom of the differential and it's not very easily read.
Whoever etched the info onto the diff. did a poor job.
There is an ink stamping of numbers about a half inch tall reading,
"21788".
The best I can tell of the etched info is as follows,
"3.07 (3 is very iffy) 43-14"(2nd 4 is barely visible and may be imagined.)
716188 if correct,is the next line and is not much better than the others.

So then I go to the vehicle info tag inside the console.
The local Chevy parts dept. sez it will say "G44 -OR- G87".
Of course mine says BOTH. :rolleyes:
So I wrote down all of the info and I hope someone can give me a definite
answer. The vehicle info is:

AC1 AC3 AQ9 BGR B3W B4P CC3 C49 C68 DL8 D3X D74 D9B
E5Z E9Z FE7 FG3 G44 G87 KC4 K68 L98 MK2 MM4 NA5 QA1
UQ4 UU8 VO1 V73 XAU Z51 ZGA 1AZ 24S 73I 732 739
8IU

That's it guys. I hope someone knows for sure.
Thanks for your help.

 

corvette_bob, G44 is for a 3.07 axle ratio and the G87 means you have an 8.50" ring gear. For conversion of the rest of your RPO codes go to http://www.thirdgen.org on the left hand side of the home page will be a Tech Central box, in there is a pretty easy to use RPO decoder. good luck !

 

Hmm. Gets interesting

According to the factory service manaul for my 92 you have 36. That doesn't make any sense, but here we go.

RPO_____ GM PART NUMBER ______ GEAR RATIO _____ TEETH, RING/PINION

DANA 36
GM1 10046613 _________ 2.59 ____________ 44:17
GU2 10046614 _________ 2.73 ____________ 41:15
G44 10046615 _________ 3.07 ____________ 43:14 **** This is probably you

DANA 44
GT7 10126418 _________ 3.33 ____________ 40:12
GM3 10126476 _________ 3.45 ____________ 38:11

In the 92 manual it says that the 36 options are auto tranny only while the 44's say manual tranny only.

It sounds to me like you've got some screwed up stuff going on there. Your RPO code says it's a dana 36, the gear ratio and tooth combo also confirms this. It would seem that you have the dana 36 in a manual, from the factory, unless of course it was converted over to a manual. One of those RPO codes will mean Auto or Manual. I just don't know which one on your year. One more thing you can check just in case. The picture in my book shows 8 bolts on the diff cover for the dana 36, the 44 only has 7 bolts.

Let us know what you find.

BTW, if G87 means 8.5" ring gear size, that makes even less sense. It says right here in my book that the 36's had a 7 7/8" gear while the 44's had the 8 1/2"

So it sounds to me like you have a completely impossible combo man. Something has to give.


[Modified by Nathan Plemons, 10:11 PM 1/12/2002]


[Modified by Nathan Plemons, 10:11 PM 1/12/2002]

 

Dana 44 on top, Dana 36 below.

 

I was hoping you would post that. I didn't remember who had that picture. What do you think is up with his RPO codes? How could he get an Auto only option with a manual. Only thing I can figure is if the car was converted to a manual.

What's the RPO code for manual in that year? I know on 92 it's MN6

 

The MM4 RPO code is the Manual four speed.

 

Ok, so that leads us further down the WTF road. I thought the only manual that came with the 36 was the 84 model year.

 

Nathan and all...

The early D44 rears were indeed 3.07 ratio stock. I know 88 was this way. I am not sure which year was the cutoff before the 3.45 gears started.

Sounds like he has a 3.07 ratio 1988 Dana 44 in his car. Nothing odd about that.

Tom Melton
82 CE
86 Z51 Coupe

 

That makes some sense but it's strange that they would keep the same option code and move that gear ratio from the dana 44 to the 36. One more thing that's odd, if he has the 8.5 ring gear because it is a dana 44, how does it work that the gear tooth ratio is the same as the 7 7/8" ring gear of the 36. How can you get the exact same 3.07 with the same tooth ratio out of a smaller ring gear? I'm no expert by any means, but I thought that the smaller ring gear would change the numbers in order to get the same ratio.

I don't doubt it, but I guess I need an explanation about how the ring/pinion tooth thing works.


[Modified by Nathan Plemons, 10:53 PM 1/12/2002]

 

Never mind, I believe I have answered my own question. If you divide the ring gear by the pinion gear you get the ratio obviously. Thus the ring size doesn't come into play. I guess the larger size is just for strength, greater heat dissipation, etc.

Well I guess you got your answer Corvette_Bob. The forum triumphs again, we all learned something in the process. Thanks Tom.

 

According to the pic posted by RAYSUR, the D-36 has only one
bolt at the very top of the batwing and the 44 has two.
I gotta put it back up on the ramps and try to feel around
to find if it's got one or two.
As for the confusion, it's just par for the course in my life. :crazy:
Maybe it's the fact that my car was pretty late in the '88 production
run.

 

Ok, here's a little more info.
I'm taling this from the service manual
I got for Christmas. It gives nothing definite,
but it gives greater credibility to the
probability of it being a Dana-44.
The manual sez the 36 is
"AUTOMATIC TRANSMISSION ONLY"
Same part # for Z51 or standard.
GM part# 14087652
3.07 ratio
Teeth no. Ring:p:inion 43:14
Cover bushing color, Black w/ Z51, Blue w/ std.
I just realised that the "21788" is the count on my VIN.
What I thought was "716188" is the
build date, 7/6/88.
I would never have thought the production run
would have run into July.
Thanks for all the help guys.

 

I don't know what to tell you. The only stick C4s to get a Dana 36 were the 1984 models. My '87 is a 4+3 & Dana 44, your '88 is a 4+3 & Dana 44.

 

:yesnod: :yesnod: :yesnod: :yesnod: :yesnod:


Unless someone changed it!!!!!!!!!!!!! :yesnod: