1991 GMC Vandura 2500 Q&A
1991 GMC Vandura 2500 Question: If a/c compressor is taken out what about the serpentine belt?
Looking at the belt route drawing http://www.2carpros.com/car_repair_information/year/1992/make/gmc/model/vandura/1992_gmc_vandura_drive_belt_routing_diagram.htm the routing between the tensioner and idler (even after you figure out which fan belt short enough to use) doesn't look like it would be possible to eliminate the compressor and still properly tension the belt. - patrick mannion
If you can make a straight line between the two adjacent pulleys, you may be able to use a shorter belt. However this will change (decrease) the friction surfaces on those two pulleys, and may cause belts to get eaten and pulleys to overheat due to belt slippage. Best bet would be to just leave the dead compressor in place and use it as an idler pulley... - Wilsonite
I have the same question for my 2001 Olds Intrigue. Looks like someone has invented a "bypass pulley" for just such a situation. I found it at this location: http://www.1aauto.com/1A/ACBypassPulley. Not sure if they make one for your make and model. Or mine. - Dan Teitsort
You can't re-route the same belt. You'd have to obtain a belt of the new correct length.....perhaps one made to fit the same exact engine that doesn't have A/C. I sugest you inquire at the dealer for availibility of correct belt before you start this. - Visitor
i have a 92 gmc vandura 2500 with the 5.7 and the correct answer is to have the system drained remove the compressor before it ceases and throws the belt or worse locks and stalls your engine on the freeway like it did mine and get the bypass pulley from a parts store mine cost about 40 bucks and make sure you secure the ac lines out of the way same belt size you just remove a potential problem - Visitor
I recomend getting the dummy pulley. If you use a smaller belt to compensate for the missing A/C pulley you have no room to tighten the belt once it wears a bit. Therefore the tensioner is key and you must have the a/c pulley or a dummy pulley - Visitor