what tranny do I have

griff · March 29, 2004

I have a 2001 GMC Sierra SLT ext. cab 2wd. Can someone tell me what model the tranny is?

thanks

Cool Zr2 · March 29, 2004

It would help if you told us if it was an auto or not.

just look for a code like M30 in your glove box, thats a 4l60-e.

griff · March 29, 2004

sorry, its a 5.3L auto

griff · March 29, 2004

it does say M30

thanks a lot

Cool Zr2 · March 30, 2004

it does say M30

thanks a lot

No prob.

OUMike · March 30, 2004

Ok....yea, I know..we've been over this. But I guess I'd like to know what the differences are. His 01' 5.3L is equipped with M30 (4L60-E) and my glove box also has M30 in it. Are there any major differences between his 4L60-E and mine?? My truck is a 94' 4.3L

Anyone know how much and where one might be able to find a 700R4? Doesn't have to be new.

Cool Zr2 · March 30, 2004

Ok....yea, I know..we've been over this. But I guess I'd like to know what the differences are. His 01' 5.3L is equipped with M30 (4L60-E) and my glove box also has M30 in it. Are there any major differences between his 4L60-E and mine?? My truck is a 94' 4.3L

Anyone know how much and where one might be able to find a 700R4? Doesn't have to be new.

There are major differences between them. His is the new case with the removable bellhousing, yours is the traditional older style case, thus the tail shafts are different and tail shaft housings are different.

Yours has a higher stall torque converter and his is not as high.

His has better clutch packs and bands.

His has a better servo package.

His has the newer style deep pan.

And you can't run a 700r4 in your truck, your transmission is a 4L60-e, the e means Electronic, so you Can't put a 700 in it without major harness and PCM modification. A 700 is the same as a 4l60-e anyway, and a 4l60-e is better. Basically if you installed a 700r4 in your truck it would not start, because the PCM will think that the transmission is not there becasue of the plug not plugged into your 4l60-e.

03GMCinBC · March 30, 2004

I also have a GMC'03 5.3 with an M30 in the glove box. My owners manual says I dont need to service the transmission if it is the allison transmission until 50,000 miles. If not it has to be done at 25,000. I asked the dealer a couple of days ago how to determine the transmission type, since i cannot find it anywhere in my paperwork and I forgot if they advised me when i bought it.

He went outside, crawled under the truck came back and said, "dosent look like an allison . Pretty unscientific i think...

Any way to tell by code on the truck somewhere?

thanks

blue2kzr2 · March 30, 2004

I also have a GMC'03 5.3 with an M30 in the glove box. My owners manual says I dont need to service the transmission if it is the allison transmission until 50,000 miles. If not it has to be done at 25,000. I asked the dealer a couple of days ago how to determine the transmission type, since i cannot find it anywhere in my paperwork and I forgot if they advised me when i bought it.

He went outside, crawled under the truck came back and said, "dosent look like an allison . Pretty unscientific i think...

Any way to tell by code on the truck somewhere?

thanks

The Allison is used behind the Duramax and some 8.1L engines. The tranny is actually made by Allison, a HD tranny manufacturer, they make units used in 18 wheelers. The typical tranny for the LD trucks is GM-built, a Hydromatic. Check www.gmpowertrain.com for a lot more info, including gear ratios and such.

Cool Zr2 · March 30, 2004

Your not gonna find a allison behind a 5.3.

You should have your 4l60-e serviced every 50,000 miles. Filter changes every 25,000 miles.

M30 is the 4l60-e, nothing else, no need to get under it.

99-2door · March 30, 2004

It would help if you told us if it was an auto or not.

just look for a code like M30 in your glove box, thats a 4l60-e.

He did tell us, SLT is only available with an auto.

BlackSilver · March 30, 2004

He went outside, crawled under the truck came back and said, "dosent look like an allison . Pretty unscientific i think...

Since the Allison only comes on 2500HD and 3500 series trucks, and then only if the engine is a 6.6L diesel or 8.1L gas, you don't have one. No need to crawl underneath and look.

If you have an automatic, then it's it's a 4L60E. There are no other options.

Cool Zr2 · March 30, 2004

It would help if you told us if it was an auto or not.

just look for a code like M30 in your glove box, thats a 4l60-e.

He did tell us, SLT is only available with an auto.

It could have been a 4L65-e.

OUMike · March 30, 2004

And you can't run a 700r4 in your truck, your transmission is a 4L60-e, the e means Electronic, so you Can't put a 700 in it without major harness and PCM modification. A 700 is the same as a 4l60-e anyway, and a 4l60-e is better. Basically if you installed a 700r4 in your truck it would not start, because the PCM will think that the transmission is not there becasue of the plug not plugged into your 4l60-e.

So what is the proper way to convert one of these trucks from 4.3L to 5.7L??

Cool Zr2 · March 30, 2004

And you can't run a 700r4 in your truck, your transmission is a 4L60-e, the e means Electronic, so you Can't put a 700 in it without major harness and PCM modification. A 700 is the same as a 4l60-e anyway, and a 4l60-e is better. Basically if you installed a 700r4 in your truck it would not start, because the PCM will think that the transmission is not there becasue of the plug not plugged into your 4l60-e.

So what is the proper way to convert one of these trucks from 4.3L to 5.7L??

Put a 5.7 in it......