# Car dopers: caravan shuddering **URL:** \ **Category:** Factual Questions\ **Created:** [August 26, 2010, 5:18pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557 "2010-08-26T17:18:33Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 26, 2010, 5:18pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/1 "2010-08-26T17:18:33Z")
Mrs. Geek’s 1996 Dodge Caravan is shuddering a bit. The weird thing is it only does it on rare occasions. It is very intermittent. Today for example, we went somewhere that was about a 20 min. drive each way. On the way down, the van shuddered once really bad about 5 min. into the trip. I thought at first that Mrs. Geek had driven over the rumble strips in the center of the road but the road was smooth and she was all the way in her lane. It did it a couple of times later in the trip, each time lasting for only a few seconds. I was paying more attention by then, and the road was smooth so I know it wasn’t just rough road conditions. On the way back, it only shuddered once, when we were almost home. I want to say it feels more like engine/transmission than wheel vibration, but it’s kinda hard to tell. The van runs perfectly other than this. 99 percent of the time there is no vibration or shuddering or anything. Ideas? ETA: The first time it shuddered today it was fairly severe, feeling almost like running over rumble strips. The rest of the times it was much more subtle. ---
**Author:** ![JerseyFrank](https://avatars.discourse-cdn.com/v4/letter/j/bcef8e/32.png) [@JerseyFrank](https://boards.straightdope.com/u/JerseyFrank)\ **Post date:** [August 26, 2010, 5:24pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/2 "2010-08-26T17:24:45Z")
Is it related to changing gears? ---
**Author:** ![curious11](https://avatars.discourse-cdn.com/v4/letter/c/ac91a4/32.png) [@curious11](https://boards.straightdope.com/u/curious11)\ **Post date:** [August 26, 2010, 5:28pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/3 "2010-08-26T17:28:36Z")
Check the drive shaft connections to the universal joints constant velocity joints. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [August 26, 2010, 6:03pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/4 "2010-08-26T18:03:15Z")
A common problem on these is torque converter shudder. Sometimes it’s necessary to replace the torque converter, but often they respond to fluid service, so try that first. In this case a flush (replaces 98% of the fluid) is probably a better choice than a traditional service (replaces filter and ~60% of the fluid). MAKE ABSOLUTELY CERTAIN THAT THE CORRECT FLUID IS USED (probably ATF+3 or 7176, but look it up and be sure). I would also add some [LUBEGARD Highly Friction Modified ATF Supplement](http://www.lubegard.com/~/C-177/LUBEGARD+Highly+Friction+Modified+ATF+Supplement) (black bottle). ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [August 27, 2010, 6:16am UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/5 "2010-08-27T06:16:41Z")
Probably a better choice of supplement: [Dr. Tranny Instant Shudder Fixx](http://www.lubegard.com/~/C-230/Dr.+Tranny+Instant+Shudder+Fixx) (still from the LUBEGARD company). ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 27, 2010, 4:00pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/6 "2010-08-27T16:00:42Z")
> [@JerseyFrank](#): > > Is it related to changing gears? I’m not sure. Each time it happened we were going somewhere around 40 or 45 mph or so. It is definitely not happening with every gear change. > [@curious11](#): > > Check the drive shaft connections to the universal joints constant velocity joints. I’ll take a look at the CV joints this weekend. > [@Gary\_T](#): > > A common problem on these is torque converter shudder. This really seems to fit the symptoms, and after poking around on the net it does seem to be a common problem with this era of caravans. If I don’t find anything with the CV joints this weekend I’ll have Mrs. Geek take it in on Monday and get the transmission flushed. This is a used minivan that we only recently bought so I don’t know its maintenance history. Apparently just putting the wrong transmission fluid in it can cause these types of symptoms. Thanks to all who responded! ---
**Author:** ![crazyjoe](https://avatars.discourse-cdn.com/v4/letter/c/f14d63/32.png) [@crazyjoe](https://boards.straightdope.com/u/crazyjoe)\ **Post date:** [August 27, 2010, 4:58pm UTC](https://boards.straightdope.com/t/car-dopers-caravan-shuddering/551557/7 "2010-08-27T16:58:22Z")
Well, while you’re looking over the CV joints, do have a look-see at the transmission fluid. If it looks burnt or smells bad, by all means that is a good indicator something needs to be done, regardless.