What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[Charlie207]

the first time I did mine it was about the worst I've ever seen on the magnet on the cover for a rear end that wasn't howling. but 2 long tows and over 40k miles ago, it's still quiet. so eh. if it's not making noise, I wouldn't touch it at along as you don't see chunks of metal. Just the paste.

Valid points.

But, suppose I wanted to upgrade the final drove of my 4x4 6L80 w/3.42 gears... where would I look for a 3.73, or so, upgrade, and what parts would I need to upgrade? (I'm not sure on the sizes/part # for the front/rear diff.)

Santa might still have me on his list....

 

[Sir_Hiro]

the first time I did mine it was about the worst I've ever seen on the magnet on the cover for a rear end that wasn't howling. but 2 long tows and over 40k miles ago, it's still quiet. so eh. if it's not making noise, I wouldn't touch it at along as you don't see chunks of metal. Just the paste.

It just alarmed me cuz we're about to get some decent snowfall and I dont wanna be calling a tow. But After reading on how the G80 actually works and I think its good. I was going around a corner slow hit some ice it locked like normal and couldnt unlock because I was in a drivethrough. My theory anyway. I will still change the fluid out in the spring or throw a Yukon in it depending on what happens.

I've never had a automobile with a Posi/locker so I'm new to all the fun new noises that come with it.

 

[Sir_Hiro]

Valid points.

But, suppose I wanted to upgrade the final drove of my 4x4 6L80 w/3.42 gears... where would I look for a 3.73, or so, upgrade, and what parts would I need to upgrade? (I'm not sure on the sizes/part # for the front/rear diff.)

Santa might still have me on his list....

I've always had good luck buying things off Rockauto drivetrain related.
USA Standard is just Yukon with very minor defects. I've been running their axles in my C10 and they handle the abuse no problem.
Buddy has Yukon Gears in his C10 and they work fantastic

 

[Charlie207]

I've always had good luck buying things off Rockauto drivetrain related.
USA Standard is just Yukon with very minor defects. I've been running their axles in my C10 and they handle the abuse no problem.
Buddy has Yukon Gears in his C10 and they work fantastic

Yeah, I'm just talking about the actual part number for the 2014 front and rear diff. I don't even know where to start for that. There's too many different size options for "2014 Yukon" on Rock Auto.

 

[j91z28d1]

Valid points.

But, suppose I wanted to upgrade the final drove of my 4x4 6L80 w/3.42 gears... where would I look for a 3.73, or so, upgrade, and what parts would I need to upgrade? (I'm not sure on the sizes/part # for the front/rear diff.)

Santa might still have me on his list....

I would be someone here has that answer. most common seems to be replacing the whole thing with a low mileage used one in the larger size.

me, I don't off road or need more rear load weight capacity so I think I'd just call up motive gear. tell them what I have and order the ring and pinion in that size. toss it in and go. but mine wouldn't work will at all with more gear. sometimes I wish my. 3.08 was a 2.73 on the highway haha. my tranny doesn't have a big over drive. it's like a 0.7something and first is functionality infinite. weird hybrid things lol

 

[j91z28d1]

It just alarmed me cuz we're about to get some decent snowfall and I dont wanna be calling a tow. But After reading on how the G80 actually works and I think its good. I was going around a corner slow hit some ice it locked like normal and couldnt unlock because I was in a drivethrough. My theory anyway. I will still change the fluid out in the spring or throw a Yukon in it depending on what happens.

I've never had a automobile with a Posi/locker so I'm new to all the fun new noises that come with it.

I've had a bunch of different limited slip diffs, but never this weird locker thing. besides the whole exploding thing if your try to put to much power thru it and use it like a normal limited slip/posi. I feel like it's kinda helpful? I mean I've seen a video on YouTube of a truck going thru a ditch with one back tire in the air, it locked the diff and drive across it like nothing. a limited slip like I'm used to wouldn't do well with that. especially 100k mile oem ones with worn out clutches and only really meant to spin both tires off the line at a red-light when new.

so I feel like it has its place, especially in a 2wd truck.

there's so many different options, what does yours have? the all time awd, or the switchable stuff? or just 2?

 

[SpareParts]

I hade a K2500 GMT800 that would lock all the time going around a corner, turning sharp in a parking lot.
If i remember right, they are supposed to lock when there is a 100 rpm difference between the rear wheels.
14 bolt G80s are actually pretty decent if you're not hammering them from stop light to stop light.

 

[thefrey]

Put new brakes and rotors on over the weekend.

Let’s just say it was time…

Brake fluid was BROWN

New PowerStop z23 coated rotors with carbon ceramic pads. Much better brake feel than metal on metal

 

[RooTBeeRthe1st]

Here's the link, if you care: https://www.americantrucks.com/barr...ner-front-bumper-with-skid-plate-s112607.html

I want a steel bumper, but don't want to expose the entire front-end of my vehicle to road salt and spray from the vehicle in front of me. The one thing the goofy Yukon bumper cover does well is wrap a plastic bubble around all the hoses, wiring, steel, and other bits that would love to rust.

Next year I'm gonna pop the grill and bumper cover off before I get my rig undercoated... i pulled the spare tire, skid plates, and four fender liners off prior to the undercoating this year, and wish I had done more. The underside of my hood is getting crusty as frig around the latch.

Appreciate it

 

[j91z28d1]

I've never in my life seen brake fluid look like that.. wow.

looks like gear lube mixed with green coolent

 

[Charlie207]

I've never in my life seen brake fluid look like that.. wow.

looks like gear lube mixed with green coolent

DOT3 & 4 mixed together, and left to absorb moisture, with an occasional boil .

 

[thefrey]

I've never in my life seen brake fluid look like that.. wow.

looks like gear lube mixed with green coolent

I was speechless when I started bleeding the rear brakes… the first few pumps looked like chocolate milk

The new brakes feel so much better with the new fluid too

 

[91RS]

I've never in my life seen brake fluid look like that.. wow.

looks like gear lube mixed with green coolent

It looked like that a lot in these if it was never changed.

 

[Charlie207]

It looked like that a lot in these if it was never changed.

Pretty sure my brake fluid looked the same the first time I flushed all four lines, after buying it. I bet new soft hoses would improve the performance & feel a lot as well. The rubber hoses are probably all swollen.

It's an easy job for this weekend if you start soaking everything in your favorite juice right now.

 

[Sparksalot]

I'm on the search for a sleek metal front (and rear) bumper. Most of them are way too bulky. My factory ones are looking *****, and instead of doing a factory replacement, I'm considering going this route. I think something low with metal bumpers would be different and pretty cool. Maybe powdercoated bronze to match my wheels. Maybe a clean version of this Move bumper.

View attachment 473174

That Move bumper is about the cleanest I’ve seen.

 

[Joseph Garcia]

My newly built 14 bolt 4.10 gear rear axle and front differential are ready for pickup and installation. Newish EBS rotors and pads will be installed on the rear axle.

More smiles per mile are coming........

 

[OBSandaNNBS]

Put new brakes and rotors on over the weekend.

Let’s just say it was time


Brake fluid was BROWN


New PowerStop z23 coated rotors with carbon ceramic pads. Much better brake feel than metal on metal

Eh, there was still some meat on those pads...

Nice job using the Welcome mat to protect the garage floor

 

[Charlie207]

My newly built 14 bolt 4.10 gear rear axle and front differential are ready for pickup and installation. Newish EBS rotors and pads will be installed on the rear axle.

More smiles per mile are coming........

View attachment 473638

Need some more details:

Who did the work, what parts (P#s, brand, etc...), costs associated?

Did you have 3.42 previously and G80, and upgraded?

 

[Joseph Garcia]

I originally had 3.42 gears, and a 10 bolt G80 rear axle.

The 14 bolt rear Axle came from LKQ, originally from a 2007 Escalade 2WD, and it cost $450 including freight. The front differential was originally in my truck, but it was failing, so it was replaced by a low mileage used one, but I kept it for a 'future' use (which is now).

The shop doing the rebuild/conversion is a little shop in NH called Prince Transmissions. The rebuild/conversion cost $4047. I have another shop, Go Auto in NH, the same one that installed my supercharger, that will install this rear axle and the front differential, and re-tune the truck at an additional cost.

The rear axle is no longer a G80, but instead it is a Detroit Truetrac with a set of 9 1/2" gears in it. The shop is not a fan of G80's, and they said the the Detroit Truetrac is stronger and better than a G80. The shop builds gear sets for performance cars and trucks, so I trust their judgment.

 

[Charlie207]

I originally had 3.42 gears, and a 10 bolt G80 rear axle.

The 14 bolt rear Axle came from LKQ, originally from a 2007 Escalade 2WD, and it cost $450 including freight. The front differential was originally in my truck, but it was failing, so it was replaced by a low mileage used one, but I kept it for a 'future' use (which is now).

The shop doing the rebuild/conversion is a little shop in NH called Prince Transmissions. I'm currently $2100 into the conversion, but I don't know yet if that is the final cost, probably not. I have another shop, Go Auto in NH, the same one that installed my supercharger, that will install this rear axle and the front differential, and re-tune the truck at an additional cost.

The rear axle is no longer a G80, but has some Eaton-type (I think) set of 9 1/2" gears in it, and I will get and post additional details on the gears when I pick it up. The shop was not a fan of G80's, and what I will have is supposed to be much stronger and better than a G80. The shop builds gear sets for performance cars and trucks, so I trust their judgment.

Awesome, thanks for the details. I assume those shops are down near the seacoast?

Im up near Lebanon, and am still looking for a good/reasonable speed shop and/or a place that can fine-tune BBPs on a dyno or road-tune.

I get that G80s aren't regarded for performance stuff, but I don't hear about them exploding as much as Internet-lore suggests. Your rug is gonna rip after the upgrade.