What did you do to your NBS GMT800 Tahoe/Yukon Today?

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bigdog9191999

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I know I am newer here, but I have always enjoyed the closeness that you get on a forum that you just don't seem to get on other platforms. there are several forums that I was part of and most just have mods/owners that just fall away and everything gets shut down. there is a few of us from some pages that have stayed in touch, but so many that have not.
 

Dantheman1540

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Long story short I have a 2003 Tahoe being delivered tomorrow for a buddy that needs a cheap beater when he gets back from Cuba. All I know is that it has around 230k, is 2wd, has the exhaust cut off behind the cats, and the tranny leaks so bad that it's gonna show up dry. So the first order of business is pressure wash and fix tranny leak, the PO says it leaks from the tail shaft seal but I know nothing about 4l60s. Is the tail seal a common spot to leak? Or should I plan to drop the pan, change the filter, and maybe throw in a corvette servo?

The goal is just to get it daily driveable for a few months then he will flip it later on this year. He paid $1500 for it, this is the only pic I have.

Also was told it's a fully loaded LTZ but we all know LTZ wasn't a thing for NBS, maybe he will get lucky and it has captain chairs and the other good interior bits.

IMG_20210415_090828_153.jpg
 

clandr1

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Long story short I have a 2003 Tahoe being delivered tomorrow for a buddy that needs a cheap beater when he gets back from Cuba. All I know is that it has around 230k, is 2wd, has the exhaust cut off behind the cats, and the tranny leaks so bad that it's gonna show up dry. So the first order of business is pressure wash and fix tranny leak, the PO says it leaks from the tail shaft seal but I know nothing about 4l60s. Is the tail seal a common spot to leak? Or should I plan to drop the pan, change the filter, and maybe throw in a corvette servo?

The goal is just to get it daily driveable for a few months then he will flip it later on this year. He paid $1500 for it, this is the only pic I have.

Also was told it's a fully loaded LTZ but we all know LTZ wasn't a thing for NBS, maybe he will get lucky and it has captain chairs and the other good interior bits.

View attachment 276500

Could be the rear output shaft seal (GM 24232325) leaking. Mine failed when I pulled the driveshaft after 15 years and 200k+ miles (the seal was old and brittle and finally gave out due to the trauma). It was easy enough to fix - took about 30 minutes total. However, I would plan on a filter change while you're at it since you can get the filter and gasket for about $30.

As for the corvette servo, I'm afraid I have no experience there so I can't make a recommendation. I've been lucky - my transmission is still all original.
 

Dantheman1540

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Could be the rear output shaft seal (GM 24232325) leaking. Mine failed when I pulled the driveshaft after 15 years and 200k+ miles (the seal was old and brittle and finally gave out due to the trauma). It was easy enough to fix - took about 30 minutes total. However, I would plan on a filter change while you're at it since you can get the filter and gasket for about $30.

As for the corvette servo, I'm afraid I have no experience there so I can't make a recommendation. I've been lucky - my transmission is still all original.

I did not realize the filter and seal were so cheap. As soon as I can rule out a cracked case or something crazy I'll get those ordered. Thanks for the info!
 

TheAutumnWind

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Long story short I have a 2003 Tahoe being delivered tomorrow for a buddy that needs a cheap beater when he gets back from Cuba. All I know is that it has around 230k, is 2wd, has the exhaust cut off behind the cats, and the tranny leaks so bad that it's gonna show up dry. So the first order of business is pressure wash and fix tranny leak, the PO says it leaks from the tail shaft seal but I know nothing about 4l60s. Is the tail seal a common spot to leak? Or should I plan to drop the pan, change the filter, and maybe throw in a corvette servo?

The goal is just to get it daily driveable for a few months then he will flip it later on this year. He paid $1500 for it, this is the only pic I have.

Also was told it's a fully loaded LTZ but we all know LTZ wasn't a thing for NBS, maybe he will get lucky and it has captain chairs and the other good interior bits.

View attachment 276500
definitely do the Vette servo. Easy $20 mod.

If it leaks that bad it could be on its way out...
 

TheAutumnWind

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So I've resealed the hydroboost twice now. Still leaks. Any tips or tricks? Maybe I'm just buying the wrong seal kit?
 

Dantheman1540

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definitely do the Vette servo. Easy $20 mod.

If it leaks that bad it could be on its way out...

It's very possible the tranny is on its last leg but anything to keep it holding on a little while longer will be the goal. I'll have to research the corvette servo more, I did a quick google search and found kits with multiple parts around $60-$80. I have no idea what I'm looking at tho so I guess I need to go to the stickies page.
 

latvius

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It's very possible the tranny is on its last leg but anything to keep it holding on a little while longer will be the goal. I'll have to research the corvette servo more, I did a quick google search and found kits with multiple parts around $60-$80. I have no idea what I'm looking at tho so I guess I need to go to the stickies page.

Fixing the leak and keeping it full of fluid will make it last longer, I don't see the point of installing a corvette servo on something you plan to get rid of, nor do I see how it will make a transmission hold a little bit longer. Now if you plan to keep it and want to reduce wear that's different.
 

NoReverseYukon

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I kept getting the ABS and BRAKE warnings which never seemed to throw a code and would disappear the next time I turned the key.
Decided to clean up the grounds and see if that does anything. While under there, I noticed how rusty the frame is and how bad the brake and power steering lines are.

I see in my future the next things on my to-do list :mad:
 

treehan77

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20 bucks says your ABS module has bad solder joints. Easy cheap fix. Need a soldering iron, solder and flux, and some RTV to reseal it after cutting the case open.

edit: hopefully all that rust doesn’t make it a PITA to get the screws out for the module, they’re already tricky
 

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