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1999 Mazda b4000 Repair Question


Topics covered: Driveshaft, Vibration, Cv joint.
Mileage: 108,000 miles.

Asked on December 10, 2011

Hard knock, extreme vibration at highway speeds

I have a 1999 Mazda B4000 4X4. I was driving home on the freeway he other day and there was a loud knock and a violent vibration came through the truck. I got off the freeway and stopped, so did the vibration. I got back on the freeway and when I got up to speed it happened again. When I drive in 4WD Hi on the freeway or 2WD under 45 I don't seem to have problems. Any help would be appreciated
Avatar Asked by Calguard11a

Answer

Replied on December 10, 2011

Check the U-joints and driveshaft yokes for play.

Tiny Answered by rivermikerat (expert)
5,494 answers provided
Replied on December 10, 2011

I'm sure I can google that. Is it safe to drive at sub-freeway speeds?

Tiny Response from Calguard11a
1 question asked
Replied on December 10, 2011

Raise the vehicle and shake the driveshafts. They shouldn't move (up and down/side to side) more than 1/8 of an inch at the yokes. Fronts are actually CV joints (constant velocity) See first image. I'm unable to find any images for the rear driveshaft.

Tiny Answered by rivermikerat (expert)
5,494 answers provided

Replied on December 10, 2011

I wouldn't drive it too long. You can do more damage, even at sub-freeway speeds.

Tiny Answered by rivermikerat (expert)
5,494 answers provided