New Gears For Towing With Gmt900

sambuhler · October 19, 2008

I noticed there have been some posts about new gears - I want to ask this with regards to towing capacity.

I am interested in towing a travel trailer, however I have a NNBS 2007 Extended Cab Standard Bed WT 2WD with the factory tow package. However, I have the 4.8L with the 3.23 rear axle ratio. The maximum towing capacity is 4700lbs.

What are your thoughts on getting the 3.73 or 4.10? If it is done at a Chevy dealer would my warranty remain?

How much would a dealer typical charge for this to be done?

Anyone had this done to their truck to increase towing capacity? Thoughts?

Zembonez · October 19, 2008

Anyone had this done to their truck to increase towing capacity? Thoughts?

If you go to the GM site and look, the tow rating does vary a lot depending on which gears you have. I would think that a GM dealer would do them and keep the warranty intact. I do not know what the cost of that would be. Probably about twice what it could be done anywhere else for.

I'm ordering 3.73s this week to replace my crappy 3.23s. I just want better performance though. All I ever tow is a boat.

Outbacker · October 19, 2008

In theory it sounds plausible, but I would seriously call your GMC service manager and ask him these exact questions.

I looked at the 2007 Trailer Life tow ratings and if I got it right, then you are good for 5900 pounds.

Silverado/Sierra 1500 Ext Cab 4.8L V-8 5,900 (a,o,z)/

2WD Standard Bed 5,900 (a,o)

a= automatic tranny

o=3.23 ratio

http://www.trailerlife.com/towratings/07towratings.pdf

I may be looking at the wrong thing, and if I am then I apologize.

Anyway, check with your service dude and he may be able to give you all the answers you need. And upgrading to the 3.73 ratio will give you an extra 1000 pounds.

TheUnforgotten06 · October 20, 2008

I noticed there have been some posts about new gears - I want to ask this with regards to towing capacity.
I am interested in towing a travel trailer, however I have a NNBS 2007 Extended Cab Standard Bed WT 2WD with the factory tow package. However, I have the 4.8L with the 3.23 rear axle ratio. The maximum towing capacity is 4700lbs.

What are your thoughts on getting the 3.73 or 4.10? If it is done at a Chevy dealer would my warranty remain?

How much would a dealer typical charge for this to be done?

Anyone had this done to their truck to increase towing capacity? Thoughts?

I called my service dept. and got an estimate for labor and he quoted me $400 w/o parts. I want the 3.73s or 4.10's. With your 4.8 Id personally go with the 3.73s, going from 3.23's to 4.10's would be a huge jump but they would still work of course. When I asked them about warranty issues they "said" that if my drivetrain would ever fail it would not be covered in my factory warranty due to the VIN details and setup not matching. But I would still find out if another dealer says something different.

Zembonez · October 20, 2008

I called my service dept. and got an estimate for labor and he quoted me $400 w/o parts. I want the 3.73s or 4.10's. With your 4.8 Id personally go with the 3.73s, going from 3.23's to 4.10's would be a huge jump but they would still work of course. When I asked them about warranty issues they "said" that if my drivetrain would ever fail it would not be covered in my factory warranty due to the VIN details and setup not matching. But I would still find out if another dealer says something different.

Speculating over the warranty is just plain silly.

IF the engine or transmission (for example) had an issue during the warranty period, they are not going to rip apart the rear axle and count the teeth to see what ratio it is. Unless you announce it, there is actually no situation that can imagine that would be a warranty concern... short of the rear axle assy itself. It's imply isn't worth worrying over.

TheUnforgotten06 · October 20, 2008

But if you do it at that same GM service dept. they will have on file that they changed out the rear gears. And not to mention if you do change out your rear gears at the GM they would have to reprogram the computer to your new gear ratio. But like I said Im just passing on what the dealership told me because if i find out better news I will probably do mine (after the Blackbear Tune of course). So thats my $.02

Zembonez · October 20, 2008

So thats my $.02

Yeah... not saying what you said was wrong at all. It's just all the more reason to go get it done by a competent independent shop and not mention it to the dealer... that's what I meant.

TheUnforgotten06 · October 20, 2008

So thats my $.02

Yeah... not saying what you said was wrong at all. It's just all the more reason to go get it done by a competent independent shop and not mention it to the dealer... that's what I meant.

Oh yeah I already located a differential shop lol and not to mention if i do end up doing it i will be using high grade aftermarket ring and pinion...no oem.

Zembonez · October 20, 2008

Oh yeah I already located a differential shop lol and not to mention if i do end up doing it i will be using high grade aftermarket ring and pinion...no oem.

I'm looking at Richmond and Strange. Got a preference?.. or a better way to go? I'm gonna order a set this week.

TheUnforgotten06 · October 20, 2008

I was looking at Precision Gear. They put their gears in race cars and stuff....so im assuming that it is good quality.

TheUnforgotten06 · October 20, 2008

They also make a 3.90....thats interests me. A 39 ring with a 10 pinion.

Zembonez · October 20, 2008

They also make a 3.90....thats interests me. A 39 ring with a 10 pinion.

I see that. $167.50 ain't bad either! Here is a link I found. I don't know anything about the company.

Precision Gear

66nova · October 20, 2008

Oh yeah I already located a differential shop lol and not to mention if i do end up doing it i will be using high grade aftermarket ring and pinion...no oem.

I'm looking at Richmond and Strange. Got a preference?.. or a better way to go? I'm gonna order a set this week.

I currently have Richmond in my nova with a 10 bolt. I have had them in the car for about 2 years now and they have held up great so far. That with 600hp small block lauching at 3500 rpm's with slicks. My dad runs a precision gear (3.90's) in his 69 camaro that runs mid to high 9's and they have been in his car about 6 years now. I personally have not ran any thing with Strange gears. I ran a number of sets of there axles, but not gears.

For any of your trucks I don't think you can go wrong, the key is the set up. Making sure they are shimmed right.

2000DV4.8 · October 20, 2008

Oh yeah I already located a differential shop lol and not to mention if i do end up doing it i will be using high grade aftermarket ring and pinion...no oem.

I'm looking at Richmond and Strange. Got a preference?.. or a better way to go? I'm gonna order a set this week.

I currently have Richmond in my nova with a 10 bolt. I have had them in the car for about 2 years now and they have held up great so far. That with 600hp small block lauching at 3500 rpm's with slicks. My dad runs a precision gear (3.90's) in his 69 camaro that runs mid to high 9's and they have been in his car about 6 years now. I personally have not ran any thing with Strange gears. I ran a number of sets of there axles, but not gears.

For any of your trucks I don't think you can go wrong, the key is the set up. Making sure they are shimmed right.

You can't just leave us with that teaser about the Nova, we need LOTS of pictures, and possibly a launch video.

While you're at it, take some more pictures of that stepside, I've been drooling over that thing since you joined.

66nova · October 20, 2008

Oh yeah I already located a differential shop lol and not to mention if i do end up doing it i will be using high grade aftermarket ring and pinion...no oem.

I'm looking at Richmond and Strange. Got a preference?.. or a better way to go? I'm gonna order a set this week.

I currently have Richmond in my nova with a 10 bolt. I have had them in the car for about 2 years now and they have held up great so far. That with 600hp small block lauching at 3500 rpm's with slicks. My dad runs a precision gear (3.90's) in his 69 camaro that runs mid to high 9's and they have been in his car about 6 years now. I personally have not ran any thing with Strange gears. I ran a number of sets of there axles, but not gears.

For any of your trucks I don't think you can go wrong, the key is the set up. Making sure they are shimmed right.

You can't just leave us with that teaser about the Nova, we need LOTS of pictures, and possibly a launch video.

While you're at it, take some more pictures of that stepside, I've been drooling over that thing since you joined.

Thanks Man! I love them both. They are my stress relief. I will get some pics for you soon and I will see if I have any good videos.

The truck I have had for 12 years, my dad and I repainted it in the shop you see in the back ground about 2 1/2 years ago. I hate to, but I think I'm going to put it up for-sale. I have a baby coming in Dec and it is just going to end up sitting and it needs to be drivin.