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

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05Single

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Chubbs

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image.jpeg New drive belt won't fit. Tad bit smaller than the original but everything says this is supposed to work. is anybody aware of a hack like heating up the belt before you try to route it on there? Only problem is it takes too long to get the belt into position; it would be back to air temp when I finally got to the tensioner.

Part number is correct so all I can do is spend more money to return it then buy a different make. Seems like a lot of trouble for something fairly insignificant, right? I got too good of a deal on this piece to now start jumping through hoops but in my experience bargains come back to bite me in the a$$
 

Tonyrodz

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View attachment 192613 New drive belt won't fit. Tad bit smaller than the original but everything says this is supposed to work. is anybody aware of a hack like heating up the belt before you try to route it on there? Only problem is it takes too long to get the belt into position; it would be back to air temp when I finally got to the tensioner.

Part number is correct so all I can do is spend more money to return it then buy a different make. Seems like a lot of trouble for something fairly insignificant, right? I got too good of a deal on this piece to now start jumping through hoops but in my experience bargains come back to bite me in the a$$
I bought a replacement belt for my 03, just because it was old. I already had replaced my alt for a higher amp and everything was good. Well, the replacement, which the book said will fit, didn't. It was a hair too short. I had to bring my old belt to compare the size. I had to go 2 sizes bigger. Sometimes these trucks are just oddballs I guess. Did you compare it to your old belt?
 

TheAutumnWind

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I bought a replacement belt for my 03, just because it was old. I already had replaced my alt for a higher amp and everything was good. Well, the replacement, which the book said will fit, didn't. It was a hair too short. I had to bring my old belt to compare the size. I had to go 2 sizes bigger. Sometimes these trucks are just oddballs I guess. Did you compare it to your old belt?

The higher amp alt likely has a larger pulley to increase alt output at idle. Sometimes this requires a bigger belt. Ive installed overdrive alt pulleys and been lucky enough to have the belts fit though.
 

Fless

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That's exactly the belt I put on my '04 5.3L with the 145 amp alternator (RPO KG3), except the belt I picked up had the newer Continental Elite labeling.

Is there a number on the belt, and does it match the sleeve number? Any numbers on the old belt?

From what I read, the 145A alternator takes the belt number on the sleeve (93 inches), but the 105A alternator takes a shorter one (~92.2 in.), 4060922. Maybe a mixup in packaging?

Not sure if they offered a bigger alternator or if yours could have been upgraded.
 

select127

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The higher amp alt likely has a larger pulley to increase alt output at idle. Sometimes this requires a bigger belt. Ive installed overdrive alt pulleys and been lucky enough to have the belts fit though.

The higher amp alt would most likely have a smaller pulley
 

Fless

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Why would a lower amp alt have a shorter belt then?

EDIT: the answer is that the alternator case is smaller for the 105a alternator. Even though the pulley diameter is larger (at 2.3") than the 145a alternator (at 2.2"), the distance between the mounting point and the pulley center is shorter. Hence a shorter belt is needed.

This in no way answers the question as to why the Gatorback belt doesn't fit @Chubbs's engine.
 
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