Lugging/Shuddering of engine

Scandia XC90 · Post by **Scandia XC90** » 18 Oct 2011, 14:09

I recently purchased my first 2005 Volvo T5 XC90 AWD w/ 84,000 and newer tires. It seems there is a shuddering or lugging of the engine when accelerating, most noticeabley between the 40-60mph. Especially when climbing a hill or steady grade incline. There always seems to be a slight shudder even at highway speeds, but not as noticeable. Also you really need to be a on well paved smooth road in order to feel for the suddering, on a rough road it's hard to notice. The shuddering is not in the steering wheel, I can feel in the body of the vehicle. There is no check engine light on. The Volvo dealer I brought it to really has no idea what could be wrong, stating there is really no way to address the problem. There reason's are that the computer codes will not be able to pick up any faults in the system. I've spoke with a couple mechanics, one mechanic stated over the phone it could be a CV joint somewhere. The other mechanic stated it could be not using premium fuel or a minor issue with the torque converter that isn't serious enough to have the check engine light come on. Any ideas would be greatly helpful, really want to fix this annoying problem without fixing parts that don't need to be fixed. Thank you.

MixEngineer · Post by **MixEngineer** » 31 Oct 2011, 09:58

Try manually shifting (pull the stick to the left to get into manual mode) from 4th to 5th and see if that improves the "shudder." If so, then your transmission may need servicing/flushing or is getting a little out of kilter. I'm curious if this clears up the issue (shifting from 4th to 5th).

Scandia XC90 · Post by **Scandia XC90** » 08 Nov 2011, 20:43

It actually seems to be most noticeable when accelerating with the manual going from 4th to 5th gear. Once it was in 5th gear it doesn't seem as noticeable. I had the ignition coil replaced and spark plugs replaced, I wonder if the mechanic would have missed something. The lugging/shudder is definitely most noticebale upon accelerating in 4th gear then seems to even out in 5th gear. Any suggestions will be helpful. Thanks, John

There is no engine light on.

Post by **boosted5cyl** » 11 Nov 2011, 12:56

Sounds like driveline to me. You wont always feel a driveline shudder though the steering. If you peg the gas does it get louder? Does the shudder seem to be directly related to road speed and load. Does the noise dissappear when you release the gas pedal?

Torque converter is another one, now is a good time as any to check your fluid level and condition.

Post by **jimmy57** » 11 Nov 2011, 13:02

Have the rear drive shaft removed and lube the front joint. The grease drying up and binding that CV joint is first noticed as this feeling. The catalytic converter heat does a number on the grease in that joint and turns it into something about the viscosity of tar.
Done soon enough, this will eliminate the need for much more expensive repair or replacement of the shaft.