The driveshaft spun in an oblong motion

SHELBS

MEMBER
2003 LINCOLN LS
3.9L
V8
AUTOMATIC
149,000 MILES

I replaced the transmission around 2-3 weeks ago. When installing the driveshaft, I noticed that the driveshaft spun in an oblong motion instead of straight. Due to improper spinning of the driveshaft, the rubber coupling/flex plate got chewed up and the metal support pieces in each bolt hole separated from coupling causing the driveshaft to separate from the transmission. So I went yesterday and got a new driveshaft and replaced that. While turning the driveshaft by hand and watching how rotate I noticed that it still spins in an oblong motion. What am I suppose to do to correct this problem so I don't continue wear/tearing the rubber coupling/flex plate apart? Also can u send me a link or video on how to properly check and fill transmission fluid? (The image is from the tow truck driver right after it broke)

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1 Reply

KEN L

MASTER CERTIFIED MECHANIC
42,967 POSTS

The driveshaft needs to spin true. can I ask if the driveshaft is bent or the carrier bearing is out? I would get a rebuilt unit and install it. Here is a guide to help you step by step with instructions in the diagrams below to show you how on your car:

https://www.2carpros.com/articles/how-to-remove-a-drive-shaft

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem. Please start a new question for the transmission fluid issue.

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