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Serpentine belt- when to replace?

19K views 28 replies 18 participants last post by  bullethole 
#1 ·
I remember the belts go for a long time....
My belt was replaced at about 46,800 when my water pump failed(bearings) and the fan wobbled like crazy. this causedthe edges of the belt to get worn out- so it was replaced.
Im now at 91,400 - and wondering if this belt with 45,000 miles is ready to be replaced.
I looked at it. Looks a little brown along the grooves.- but dont know if thats normal- cant really see any cracks.
what are you all doing?
 
#2 ·
I just replaced the one on my wife's 02' and it has 91K on it. It was beginning to crack on the grooved side and was stretched a little as well as starting to glaze. I really don't think any less than 90k for a replacement on this is required and IMO it could have gone easily another 10-20K on the original.
 
#4 ·
did a search- but how do your replace it.
Seems its releasing tension on tensioner---- but how do you do that?
anyone have pics?
 
#5 ·
You should be able to release the tension by using a socket ratchet set up on the tensionometer. I haven't done it on the TB/EN though. GM says to change them at 150k which is a little too long for me so I change mine at 75k. At 150k I would also change the water pump and tensionometer if they were not changed already.
 
#6 ·
hmmmm. so at 45,000. the belt is still young...
though harder to see small defects on the grooved side as compared to the old V-belts.
 
#8 ·
I've never actually seen a serpentine belt break! Every 'failure' I've seen on serp belt equipped vehicles was caused by a bad idler pulley bearing, tensioner, waterpump, etc... never the belt itself! They last a very long time. Dealers love to recommend a replacement as it's a super easy money maker for them.

Joel
 
#9 ·
I was under the impression it was at 100K as well as a rule of thumb. Although mine is now at 100K+ it still looks good,hhmmm....wonder if the lady who owned it before me replaced it or if it was replaced before I bought it used at the dealer.

But from what I have always heard....100K.
 
#22 ·
Jimmy do you recal if it was just the belt alone that was the issue, or was it one of the pullies? Another example of serpentine belt toughness just came to mind. A buddy of mine had an S10 blazer 4.3L some years ago (he's not a car guy :rolleyes:). Had a siezed idler pulley bearing for around a week. The serp belt slid over that locked up idler for a week until he couldn't stand the noise anymore! The belt was burned and frayed a bit, but not even close to breaking. He had a shop do a new tensioner, idler and belt all at once.

Joel
 
#16 ·
I think ill buy one- ($32 at the local AC delco place)
and carry it with me as I drive cross country into Mexico.....
that should alleviate some concern. and its light and compact enough to carry- Ill place it next to the jack under the seat.
 
#21 ·
so I can stick one of the bigger sized ratchet, and get a pipe, slide it on to the ratchet handle and turn clickwise.....
If I recall, theres a diagram of the serpentine location on a decal under the hood?
 
#24 ·
I was planning on changing mine at 49K last year when I did a lot of work, but my original belt was fine so I didnt waste the money and returned it. After my PS pump failed, I went ahead and replaced it just for peace of mind.

I actually put my old belt on, and the tensioner was waaaay lower (to pull up more slack) than when I put the new belt on. Now, my tensioner is pretty level instead of tilted down b/c it isnt compensating for a really loose belt. I think my old belt is between .5-1in longer than the new belt (proper belt, I bought it from a stealership).
 
#25 ·
I actually put my old belt on, and the tensioner was waaaay lower (to pull up more slack) than when I put the new belt on. Now, my tensioner is pretty level instead of tilted down b/c it isnt compensating for a really loose belt. I think my old belt is between .5-1in longer than the new belt (proper belt, I bought it from a stealership).
Really good point. As Joel said these belts rarely ever break, but they DO stretch. I don't know about the Tb, but my Ford has marks on the tensioner to indicate if the belt is stretched or not. Once it gets past a certain mark you are suppose to replace it.
 
#29 ·
Mine is three years old and 98k. No cracks or fraying anywhere. Check it once a month. Probably change it soon to be safe. The old trick of using panty hose as an emergency replacement doesn't work on serpentines.:crazy:
 
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