not sure what gears or trans are in my truck

[aml396]

I just bought a 1989 chevy K 2500..it is 4x4..it has a 350 in it.
Can anyone tell me if that has the 350 or 400 transmission?....its a 3 speed automatic
I do know that everything in it is stock
Also would that have 3.73 gear or 4.10 ? Thanks for any help that anyone may have

[sntrym95]

Look in the glove box. Here are the axle codes:

GU2 = 2.73
GU4 = 3.08
GU5 = 3.23
GU6 = 3.42
GT4 = 3.73
GT5 = 4.10

[Alderson95]

Ill bet 10 dimes to a dollar its a gt5 simi flow 14bolt rear with 4:10
Posted via Mobile Device

[aml396]

Originally Posted by sntrym95

Look in the glove box. Here are the axle codes:

GU2 = 2.73
GU4 = 3.08
GU5 = 3.23
GU6 = 3.42
GT4 = 3.73
GT5 = 4.10

Yeah ...problem is that its all worn off ...feels like 4.10...winds up pretty good....course it is a 3 speed. She slows down pretty good when I let off the gas,,,,feels like 410....I cant seem to find anyway to get it from the vin either.....do you think its 400 trans ? I do know that it is the heavier 8600 GVW

[aml396]

Originally Posted by Alderson95

Ill bet 10 dimes to a dollar its a gt5 simi flow 14bolt rear with 4:10
Posted via Mobile Device

yeah....feels like it...its the heavier 8600 gvw too...I mean ift that helps you to know.... do you think its a 350 trans or 400 ?

[Alderson95]

u can chek by jaking up the rear of truck and have someone put it in gear and watch the driveshaft if it turns 4 times to 1 wheel revolution that should be the 4:10

[aml396]

Originally Posted by Alderson95

u can chek by jaking up the rear of truck and have someone put it in gear and watch the driveshaft if it turns 4 times to 1 wheel revolution that should be the 4:10

thanks...gotta be a fool proof way there

[loudnlifted88]

type your vin number in here.....http://www.compnine.com/vid.php should come up with all the options your truck got from factory

[aml396]

Originally Posted by loudnlifted88

type your vin number in here.....http://www.compnine.com/vid.php should come up with all the options your truck got from factory

Nah...it didnt work...xaid it didnt have it in thier data base
Vin is 1GCGK24K6KE189789

[TURFKING]

Crawl around with a strong flashlight and see if you can find any,any numbers or tags on it. Could get lonely and ugly under there all by yourself but that may be your only route. Pic's would help the experts on this site to help ID what you got.

[aml396]

Originally Posted by TURFKING

Crawl around with a strong flashlight and see if you can find any,any numbers or tags on it. Could get lonely and ugly under there all by yourself but that may be your only route. Pic's would help the experts on this site to help ID what you got.

thanks man

[67c10rustbuket]

The RPO codes for the axle ratio should be on the glove box sticker, idk how that would get worn off ? too many wrenches sliding around in the glove box? thats how i found my 93 has 3.42 limited slip rear gear. if nothing else pull the diff cover GM usually stamps the ratio on the ring gear , if not you can count teeth and divide. but that method will cost you a gasket and some gear oil, but its foolproof especially if it has been changed over the years... you can identify the trans by the shape of the trans pan. i think a Th350 is a square with one corner @ 45degrees.

[67c10rustbuket]

I cant get my MAC to paste a pic of the trans pan ID, just google "GM trans ID" and you will find plenty of pics showing which pan is for each trans. later

[dishow]

http://www.decodethis.com/Default.as...GK24K6KE189789



according to this,it came factory with a 4 speed overdrive.

[aml396]

Originally Posted by dishow

http://www.decodethis.com/Default.as...GK24K6KE189789



according to this,it came factory with a 4 speed overdrive.

nope.... it came stock out of the factory with 3 speed...its either a 350 or a 400 trnas....just dont know which..,..yet.....problably the 400 because it has the heavier of 2 GVW for that truck....8600 GVW

[dragginmetal]

[aml396]

Originally Posted by dragginmetal

Attachment 785990

NICE !! there will be NO question on that now. I dont even have to drop the pan yet if I dont want. The location of the module tells it
.....GREAT>...thanks a ton.....well...... a 3/4 ton !!

[aml396]

thanks alot man...that did it....its a 400. Thats one very EASY way that I will never for get.The shape of the pan is enough but the position of that module makes it a dead give away. The modules sticken out of the side so its a 400.
Now ive gotta be certain about the gears ....feels like 410 but I just gotta know. she feels and sounds pretty wound out at 70 and when you let off the gas it slows down pretty good but then again its only 3 speeds in the trans. love the truck though...350's GOTTA be one of the best motors ever produced by anyone. That 400 trans with the 410 gears in the rear prob one of the best drive tranes too....thanks again

[dragginmetal]

No prob. Glad you got it figured out.