2000 V70 XC clunks and jolts accelerating through 55 mph

sorenmail · Post by **sorenmail** » 28 Sep 2009, 10:42

When accelerating from a stop through 50-55 mph my 2000 V70 XC (155k miles) makes a clunking sound and feels like I ran over something in the road. It seems to be coming from the rear end but I'm not positive. I replaced a broken upper engine mount but that didn't fix the problem.

Once I pass through 50-55 mph and it experiences the clunk it doesn't do it again if I slow down and then accelerate back up. Only when the car comes to a complete stop and then accelerates back up through 50 mph does it repeat the jolt.

Any guesses on this one?

FCPEURO · Post by **FCPEURO** » 28 Sep 2009, 11:13

Rear differential mount? Could be a drive shaft mount. The 1st gen XC70 is known for issues like this.

Post by **jblackburn** » 28 Sep 2009, 12:44

Not sure if the gears are the same in the XC as in the S/V70's, but right around 50-55 is when my torque converter locks into overdrive if I'm not climbing hills or stepping on the gas very hard. That could also be what you're experiencing. How's your transmission fluid look?

sorenmail · Post by **sorenmail** » 29 Sep 2009, 10:27

Thanks for the response. I'll check both of these items out. I'm probably due for a trans flush so I'll give it a shot this weekend. I've got an Acura Legend with 225k on it and a trans flush made it run like new.

FCPEURO · Post by **FCPEURO** » 29 Sep 2009, 12:40

A trans flush is the best thing to do for your transmission. It is amazing how many people over look it.