Minivan Repairs: Replacing the Serpentine Belt Tensioner
Allpar member joandjo purchased a 1999 Chrysler Town & Country (similar to the Dodge Grand Caravan and Plymouth Grand Voyager). He appreciated its improvements over joandjo’s 1997 (HomeLink remote, tiltable A/C vent, thicker valve cover gasket, and radio volume switch in the steering wheel, and much improved headlight design), but it had one problem: The belt was shredded at the edge, and the tensioner was making noise.
(The 1999 minivans were in the same generation as 1996-2000 models, but the serpentine belt and tensioner may have been common to newer models as well, using the 3.3 and 3.8 liter V6 engines. The latter lasted through the 2010 model year.)
He changed the belt from the old van to the new one. Within 3 miles, the belt was shredded again. Good thing that he didn't purchase a new belt. He decided to change the tensioner from the old van to the new, since he still had the old van.
He never replaced the tensioner before this, so he searched for advice. Numerous people on allpar.com saidm "remove the nut at the back from below." But he couldn't understand "the back." After he'd done it, he can say this is like a "15-minute job if you know how to do it, but a 3-hour job if you don't." So he decided to take some pictures for everyone's benefit.
The hardest task was to remove and put the belt on. Everyone had their own way. He used a daisy chain wrench setup (pictured above).
This is where the tensioner is.
But where is the nut at the back? Can you see the nut in the above picture? No one provided a clear picture yet, so here it is. It is necessary to remove this nut.
First, he removed the tensioner from the old van from the "top." It took over an hour. He chose this way since he needed to remove the alternator. The alternator in the old van was less than 17,000 miles old -- pretty new.
In the new van, he approached from "below" just to compare how easy it is. So, how to undo the nut from below? It's not hard at all if you have a proper tool setup. It took less than 5 minutes to remove.
And here is the tool setup.
15mm socket + 4" wobble extension + u-joint + 24" extension (it can be 12" extension)
Just unscrew the nut at the back and the tension will come off easily. When you put back in, place a wood block (or similar) between the tension and the inside fender to keep the tensioner in place until you tighten the nut. And that's it.
Tips from other allpar members
valiant67 said: I would do it from below. It's easier to feel for the nut than to see it. However, due to the odd angle if it's really tight it can be hard to remove due to needing a flex to get at it. In that case, you might need to remove the alternator but I'd try from underneath first. If you can round up a helper, it's nice to have the helper pull of the old tensioner and put the new one in place while you remain under the van.
chuzz agreed that from underneather is the best way, but also said using two long extensions and a universal joint on his 3/8" ratchet wasn't too bad. He said the hardest part was getting the socket through the hole to get to the nut on it.
00Molavi contributed that he used a box wrench, 15mm, with a one inch PVC schedule 40 pipe (2 ft long) to relieve the tension to take the belt off and put it back on. He also suggested keeping the hood open with a pole on the other side, toehrwise the hood rod is annoyingly in the way. His last tip was to wear gloves.
valiant67 said that he used two improvised setups to relieve the tension to take the belt off and put it back on. One way was the "daisy chain" method using two combination wrenches, 15mm is the one to git the tensioner head. The second is a nice 18" extension for his 3/8" socket set. He places this extension over the end of the forward "claw" on the 15mm combination wrench. This is the only extensions he has that will fit and not slip right off. Although special tools exist, there is no need for them.