Volvo PERFORMANCE Forum

On old reliable 245, have a vibration that becomes noticeable at about 35 mph and increases in intensity/frequency? through about 55 mph, then becomes a very noticeable low-frequency hum. Vibration/hum is road speed dependent; and not related to engine RPM; makes no difference if in gear or out. Vibration can be felt in steering wheel and in gear shift lever during acceleration. A bit more noticeable in gear shift lever when coasting or slowing.

Problem began soon after engine rebuild + accessories, but NOT BEFORE replacement of tires, drive line components, and second replacement of motor mounts.

Replaced following to correct problem:

a. 4 new tires + balance/alignment < 3k ago (Big O Tire shop). Swapped out all tires, one at a time using spare; no change in symptoms.

b. motor mounts and drive-line center carrier bearing+bushing from Volvo

c. All three U-joints new

d. Drive line/U-joints properly aligned

Mechanic thinks it is the rear-differential, but I have ridden with ear pressed onto rear deck and can hear NO noise from rear end. I would expect to hear a whine if there was a serious diff problem; same for a bad rear axle bearing.

Don't know what affect if any, but just noticed yesterday while following the 245 being driven by wife along a straight road. The car appears to crab slightly to the right; about 2 inches of left front tire was visible outboard of left rear.

Frustrated to the max!