Looking for help with 91 W-350 CTD?

[JLNNSparta]

I have a 1991 Dodge 4X4 3/4 ton pickup with a Cummins engine that I got thru a legal settlement. I am not sure what the model is, but the front end looks similar to one in the picture on the banner for this site. Anyway, my problem is that it developed a "rumble" when running if I slowed down. If I sped up, the rumble would go away. I have had one mechanic I know take a look at it and he says that the problem is the automatic transmission. I have had several transmissions go out in the Chevy's I owned before and never had one sound like this. It sounds more to me like a bolt rubbing on a housing or shield.

Has anyone ever had a similar problem? Or am I unique? Does anyone have any suggestions as to where to take it for someone who is used to working on Dodges? I live near Sparta Wisconsin.

Thanks,Jerry.

[Cheyenne Dave]

Hi Jerry,

Have you thoroughly inspected your universal joints? Isn't the W-350 a 1-ton? If so, it should have a 2-piece rear drive shaft. If it does be sure to inspect the carrier bearing as well.

C.D.

[Keith in CO]

Try posting your question on the 1st Gen portion of http://www.cumminsforum.com/forum/

I second CD's idea of the u-joint. Have you gotten under the truck and inspected the rear drive shaft to see if your u-joints are shot?

Also, changing auto trans fluid and installing a new filter isn't hard and would let you know if there is metal floating around in the trans.

[JimmieD]

OOoopppss, sorry Jerry! I gave you the wrong model designation when I said it was W-350: it's a 3/4 ton W-250, my mistake.

Glad to see 2 posts mentioning u-joints, as that was my first thought also. The other possibilities are tires or wheel bearings.

Not hard to check out the u-jpints for yourself. Just park it on flat ground with emergency brake set and crawl under there and try to twist driveshafts back and forth by hand, there should be no play in the joint! If there's slop you may have found your problem. Also check the front axle u-joints as they go bad too.

In my opinion 4WD's are more likely to require better attention to front wheel bearing lube due to the way they're often used. Greasing the front bearings is a regular part of ownership maintenance and shouldn't be overlooked. It's possible one or both of them could be causing the problem.

Did you change tires on the truck recently? Are the tires aggressive tread off road type? What shape are they in?

[Cheyenne Dave]

[QUOTE=JimmieD;31308]OOoopppss, sorry Jerry! I gave you the wrong model designation when I said it was W-350: it's a 3/4 ton W-250, my mistake.

Glad to see 2 posts mentioning u-joints, as that was my first thought also. The other possibilities are tires or wheel bearings.

Not hard to check out the u-jpints for yourself. Just park it on flat ground with emergency brake set and crawl under there and try to twist driveshafts back and forth by hand, there should be no play in the joint! If there's slop you may have found your problem. Also check the front axle u-joints as they go bad too.

QUOTE]

...I would not check u-joints in this maner. By leaving the vehical on the ground you are not fully inspecting the joints on the rear drive shaft(s). By jacking one wheel of the rear axel, one is able to rotate the drive line and check eack joint in a variety of positions. All that is required is a floor jack and lift one wheel off the ground enough to allow the wheel to turn freely.

This is not nessesary on the front axel, as far as checking the drive shaft u-joints are concerned. If the hubs are not engauged and the t-case is in 4X2, turning that shaft by hand is very easy. However, you will still need to jack each front wheel to properly inspect and service the front wheel u-joints.

There is still the possiblity that it is a loose bolt...don't overlook the t-case skid plate.

C.D.

[JimmieD]

What Dave said! [Strike 2 JimmieD....]

[Cheyenne Dave]

What Dave said! [Strike 2 JimmieD....]

I sure hope you're not keepin score, Jimmie! If so, I could be in deep doo doo...

C.D.

[JimmieD]

Ha ha, thanks Dave! This conversion/rebuild/modify project I'm doing has caused that my brain just cannot keep up with the demands I've put on it. Soon as it's over, and that's REAL soon, I'm going to do nothing but sleep and eat for a month at least!