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post #1 of 4 (permalink) Old 10-09-2011, 03:59 AM Thread Starter
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Serpentine Belt Replacement

I just replaced my serpentine belt, assuming it to be a general maintenance item and the car has 79k miles on it. I can't get over how difficult it was to do the job. Chevy did make a nice access hole through the fender to replace the entire tensioner, but not to access the 3/8 inch square hole to turn it and change the belt.

Thanks to the wonderful tight design tolerances, the clearance between the tensioner pully and metal fender frame is very small, too small to get my ratchets or breaker bars.

A double thanks to the design engineers for angling the 3/8 inch square hole such that the standard serpentine belt tool kit will not work from below unless you remove your brakes/axle/wheel hub, or from above unless you remove your air intake and motor mount!

So what to do? Probably the best bet would be to grind down a 3/8 inch ratchet so that it would fit, and then use a breaker bar from underneath. I bought the standard serpentine removal tool kit, which didn't work, and then a third 3/8 inch ratchet that looked slimmer than my other two, but that didn't work either. Then I bought a 3 piece square drive socket cap from harbor freight (Pittsburgh item 67011) that ultimately helped. The little ~3/4 inch long piece had one end that fit into the 3/8 square hole in the belt tensioner, and the other end was a 6 sided bolt head that fit onto a 9/16 inch wrench. After installing this plug, I was able to fit a 9/16 inch wrench on it from underneath the car, using one of those wratcheting gear-wrenches. The other end of the wrench was exposed enough to grab it, but it wasn't long enough for me to easily turn the tensioner. So after another hour of frustration, I was able to use a shorter, 1/2 inch drive tool from the serpentine belt kit to fit into the 9/16 inch wrench end (loosely), and allow additional leverage to turn. Not at all an ideal situation, but it worked.

So now I have a new belt on the car, after 1/2 day wasted for a job that should have taken 10 minutes. Worse yet, if the belt ever breaks on the road, its an automatic tow to a garage. Pretty pathetic and inexcusable in my book...

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post #2 of 4 (permalink) Old 10-09-2011, 05:29 AM
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Thank's Greg, I usually do that job myself and plan to save your tips.
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post #3 of 4 (permalink) Old 10-09-2011, 07:08 AM
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I use a GM serpentine replacement tool similar to this one. Just a flat bar with a 3/8'' drive welded to it at one end and a rubber handle at the other.
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post #4 of 4 (permalink) Old 10-09-2011, 02:06 PM
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I took the motor mount off and jacked up the motor by the oil pan and used a 3/8 ratchet. Took about an hour

07' LS 5 spd, bullseye S256 @ 17 psi wut?!, E85!!!, wiseco 8.9:1 pistons, eagle rods, spec stage 3 clutch, TTR motor and tranny mounts, ARK sts, Magnaflow catback, tinted windows, B&G coilovers w/ adjustable camber plates, front bowtie painted black, and ETX ME-2 rims wrapped in 235/40/18 Nitto invos.
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