The serpentine belt will not stay on my 99 Dodge Caravan when it rains. This has happened 3 times

The problem started when the alternator was replaced. The serpentine belt was replaced at that time and all the other parts in the pulley area are new as far as I know. It just so happen that about a week later a hurricane came over Atlanta. I was driving up a hill in a blinding rain storm in a not so nice part of the city when the belt failed. The power steering became very hard and the car started overheating. I got off the road just in time.



My mechanic replaced the serpentine belt for free because he thought the belt had failed because rocks form a big splash of water had caused the problem.



About 2 weeks later, I hit a small puddle of water and the belt failed again. This time my mechanic went over car carefully again. I suggested that it might be the water pump. There was a small amount of play in the water pump, but it was not leaking. We thought we had the problem solved.



We had 5 weeks with no rain. During this time the car functioned fine.



This week we had a 2 day rain storm on Monday and Tuesday. The car ran fine.



This Friday I was coming home from work in a light rain storm. I was almost home when you guessed it the serpentine belt failed again. I pulled off at the Yellow River Game Ranch. I stood on the porch of the ranch me and 3 peacocks waiting for another tow tuck.





I have a very good mechanic who has been in business a long time. We are running out of alternatives.



What else can I tell you?



The belt broke 3 times.



Water seems to be the common element.



The car is a 1999 Dodge Caravan with 200,000 plus files. The transmission was replaced 1 year ago. It has the midsize 6 cylinder engine. I think it is a 4.2.



HELP

Are the belts breaking, or running off the pulleys and getting chewed up?
has the tensioner assembly been inspected/replaced? 200K is well past it’s service limit.

Was the A/C or defroster on? If yes, that means the belt if heavily loaded when it fails. Water lubricates the belt and it slips, gets hot and fails very quickly. Install a splash guard to keep water off the belt. One other thing . The pulley’s are worn out. They don’t last forever. Especially the one on the crankshaft. This makes the belt far more prone to slipping when wet…The worn pulley can no longer grip the belt properly.

The air conditioner was not on the lats time the last time it broke.

The belts are braking

The engine should be a 3.3 or 3.8, but that is not related. This belt slipping is a common problem, google it. You can check on allpar.com too. There is a Gates belt specially designed to prevent this. I don’t remember the specifics, mine hasn’t done it yet but I AM holding my breath.

Try the Gates belt that was suggested, but also check to make sure the belt tensioner is functioning correctly. It should keep it tight enough even in rainy weather so that it doesn’t begin to slip, heat up, and fail.

Just as a followup in case you did not know the AC engages on defrost setting in many cars.

My experience has proven the cause to be the belt tenioner. Good luck.

I have the same problem. Have you solved yours? Thanks, Sam

Many mechanics are unaware of the causes of this condition. I have tried to compile all of the info that I have found surrounding this issue here. Most of this content was collected from on-line accounts.
Symptom
96 -2000 Caravan / Voyager
Serpentine belt being frequently thrown off of the pulleys while driving in any amount of snow or rain.
Cause
If any of the components along the path of this belt are having issues, this can cause problems with the belt. We are not concerned here with belt failure due to normal or predictable component wear. Belts and components should be checked regularly as part of routine maintenance. This description deals with frequent belt failure due to pulley alignment not directly associated with obvious mechanical failure.
This serpentine belt system relies on near perfect alignment between all the pulleys along the belt. ANY changes in the alignment can cause the belt to slip off of the tensioner as it does not have raised edges (side walls).
It would appear from the accounts that marginal bearing wear or other foreseeable minor tolerance changes (component replacement without shimming for perfect alignment, pulley surface wear, bearing surface wear, or mounting slippage of any of the 6 component pulley systems along the belt path) can contribute to this condition.

Dealer fixes
A qualified repair shop should have a pulley alignment checker which uses a laser beam to check component pulley alignment. However, it is obvious from accounts that not all shops are aware of the delicacy of this alignment and may recommend expensive ?shot in the dark? replacements of the individual components. Component shimming may be required.
It is my understanding that there were two Chrysler TSBs (Technical Service Bulletins) on this issue. Neither one directly addresses alignment accuracy and Chrysler may be assuming that all of its mechanics are up to date on this aspect.
TSB 07-09-99 (AllData has an article about it). Pulley guard/pulley shield" (Chrysler Part # 05003480AA). It will also need a longer screw to hold both (# 04556218). essentially this is a washer that keeps the belt from slipping off.
!!! After any of these repairs, ask the dealer to pour a small amount of water onto the belt (while running) to see if the belt will slip off. As far as I am concerned, no amount of water should cause a belt to slip out of position!

Aftermarket fixes - Gates/Goodyear
This solution has had overwhelmingly positive reviews, but be warned, the parts are $100 -$160 and you are now committed to buying specific, non-standard belts for this car from then on. The kits do come with a warning sticker to this effect. It?s a belt and pulley kit that replaces all of the smooth pulleys with grooved pulleys, and the belt is ribbed on both sides.
Gates Fix kit info:
1996-2000 3.0L V6 = 38342K
1996-2000 3.3L/3.8L V6 = 38379K.
Goodyear
1996-2000 3.0L V6 engine = 49204K
1996-2000 3.3/3.8 V6 engine = 49215K
Should be available at NAPA, Rock Auto, Amazon and CarQuest.

Aftermarket fixes - Dorman/Advance
Dorman disk covers from Advance Auto generic pulley shields This fix may also require some rework or modification of the tensioner pulley bolt and shimming arrangement.

Aftermarket fixes - GM part retrofit
Some raised edge GM pulleys can be substituted in for the Chrysler original.GM Part 14102645 - Tensioner assembly off an 87-93 S10 with the 2.8L V6
Some aftermarket GM replacement parts don’t have the raised edges to keep the belt on. Check before you buy. This fix may also require some rework or modification of the tensioner pulley bolt and shimming arrangement.

Aftermarket fixes - Rockauto /Four Seasons generic pulley retrofit
Four Seasons part #s 45970 and 45887 (plastic pulley with flange made in Korea). This fix may also require some rework or modification of the tensioner pulley bolt and shimming arrangement.