Car has 122k miles. We are prepping it to give to my 16-yr old daughter to drive. The car is otherwise flawless (clean paint, no interior rips, etc.) Had our mechanic do the complete timing components, water pump, and spark plug service about 500 miles ago. When he returned the car to us he said he noticed a “slight vibration” on acceleration and thought it was either motor mounts ($1k for lowers), axles ($900 ea), or possibly transmission.

We’ve noticed the vibration getting progressively worse. I replaced the upper rear motor mount that attaches to the upper cross member. The old one was worn but it didn’t make any difference with the shuddering.

Here are the symptoms:
1. regular acceleration, vibration is noticeable but not extreme under 45mph. Over 45 thru 60-ish mph the vibration turns to a shudder.
2. The whole car seems to shake but it does not transmit thru the steering wheel.
3. Transmission shifts properly (no hesitations, bumps, clunks, etc.) Also tested in manual mode and all seemed good.
4. No vibration when coasting.
5. I checked with a couple of indy tranny shops about a fluid/flush/filter service. Neither works on Volvos. Another euro mechanic shop said, “if it hasn’t been changed up to now, don’t change it… too dangerous.” Seemed like a strange answer since the manual doesn’t indicate a service interval unless the car is used for towing.

Questions:
1. Any idea what the cost should be for a tranny fluid service? Is the vibration likely from the tranny?
2. How hard are the other 4 motor mounts to replace?
3. How much movement should the upper motor mount cross member have at the end bushings? I can move it fairly easily by hand.
4. Where is the best source for axles if that is the problem?
5. Anything else I should look at before getting killed by the mechanic or tranny shop?

 

I have a very similar issue on a 2.4l 2005 V70. Climbing a slope between 50 and 60 is a juddering, shuddering, "are the wheels about to come off?" nightmare. Take the gas off and it's fine, but you need to have the gas down to get up a hill! Flooring it gets me closer to 70 where the problem eases off. I had the wheels rebalanced so far but no difference. Did you find out the issue of yours? thanks.

 

I'd look into three areas 1) Check the drive axles. To start at home, inspect the axle boots for tears or leaking grease. A shop can put the car on a lift and make sure they are properly fitted into the tranny 2) scan for any OBD fault codes. Misfires can make the car feel like its has a transmission issue. Besides, if you do in fact have a tranny issue, it would likely throw fault codes. 3) inspect/test for faulty motor/transmission mounts. Check Youtube for how to vids...

 

You probably have a worn cv joint in your right axle. That is usually what causes that vibration sensation in the car/steering when accelerating at your mentioned speeds. As long as the vibration stops at a steady speed or decelerating.

Common problem, replace the right axle with a GMB brand (the OEM manufacturer) to solve the problem. Or - take your chances with a cheaper brand that may not be better than what you have now! The left axle is not the "dominant" axle so it wears less.

Only replace the front and left side (front of car) engine mounts if proposed by your service provider. (if the front of engine/right side is broken, and the left/front of car is collapsed broken or leaking) Any others mount replacements may/will be a waste of your hard earned dollars.