Wierd! Just changed belts on both mine & wife's MCS's. Hers is a '03 w/50k miles & 15% pulley just like mine but I've just got 25k mi. Used Gatorback 1365 belts on both. After installing and driving, mine shows one hole fully visible on tensioner, hers is not visible. At idle, I see my tensioner spring vibrating and it looks to be more compressed than hers. Should I go with a smaller belt for hers or is the problem her tensioner? (I've got ProMini Stop Bars on both tensioners).

 

I'm not sure it is the tensioner. I have an '02 MCS and when my POS early build crank pulley sheared off, Mini replaced it with the updated one and replaced my belt tensioner as well. I ran a Gatorback 1365 and it still only shows 1/4 of a hole. I think there are too many variables in the builds to come to a concise conclusion.

FWIW, my belt doesn't slip and it's been on for 5K miles now.

 

Thanks for the response, DINAN 604. Yep, hers is the early crank pulley and I've been watching it. She's a peppy driver but doesn't really get on the loud pedal. I'll ask her to let me know if she detects any slipping. Agree that there's probably some degree of variation between vehicles, hence my ? as to whether I should install a slightly shorter belt on hers. Don't want to spend $$$ on a belt tensioner if it's not needed but don't want her to get stranded out in the "toolies" either.

 

I understand your worries. Luckily, when mine self-destructed, I was only 2 blocks away from the dealership. I think the next time I replace my belt, I'll try the NAPA 060535 belt and see if it makes any difference. You could give that one a shot.

 

You read my mind! Next size down in Gatorback is 4060530 which is too short (.7"). Like Goldilocks, NAPA 060535 may be just right!

 

I have been using the Contitech belts sized for the JCW (6pk-1374) and they fit beautifully. I have a few in stock if you want to give it a try ($20)
--Dan

 

Same thing here if I go with a stock size belt with no mods I had 1/2 hole. No problems with the tensioner so I've be playing the what size is going to work game. The problem that I see is if its almost bottomed out the belt is going to stretch and if you do get on it hard you will throw a belt at some point.

 

Dan, not doubting you but, well, now I'm really confused. A Gatorback 6PK1365 gives about 1/2 hole visible. Others say a NAPA 060535 (=1359) fits a 15% pulley best but a CONTI 1374 for a JCK works? Seems to me, that would be too loose. As for throwing a belt, I would assume that a loose belt would throw more easily than a tight one.

 

Gatorback does come in a 4060532

 

For a six-rib Gatorback the only two options are the 537 & 530. The 530 fits, but man it’s tight to push over the idler pulley, even on a 19%. I used to run Gatorbacks and noticed inconsistencies in sizing from one belt to the next; that’s just a Gatroback belt characteristic. NAPA 535 (Gates) is the correct size for a 15%, however Contitech belts last much longer than Gates. Forget about comparing sizes between brands there is no standardization in published measurements.

 

Here; http://shop.oreillyauto.com/ProductD...Number=4060532

 

I must have gotten the smallest Gatorback 537 ever made, yes the belt is stamped with the right number. Having a ^%$%N( of a time getting this thing on

If I do get it on tonight this will be the last Gatorback.