Thunk from front end - anyone else had this?

Post by **pierremcalpine** » 21 Jun 2013, 08:39

First post...Alright - I can't be the only one who has experienced this...This "thunk" only happens after having driving at least 50km. It happens most regularly on the highway when a braking is following by an acceleration. When I begin accelerating it's almost like something is being rocked backwards. It's a low volume thunk that feels heavy and comes from someone in the front end. The car is a 2003 V40 T4. I've heard of engine mounts causing these sorts of issues but I don't have any vibrations during idle (even after the 50km). Thoughts?

difflock54 · Post by **difflock54** » 22 Jun 2013, 19:36

Control arm bushes possibly worn or maybe sticking brake calipers ???

AndyB2005S40 · Post by **AndyB2005S40** » 04 Jul 2013, 19:21

Could even be a totally broken lower control arm....I had a shop do my struts some months back, and shortly thereafter, felt the "thunk"' similar to what you describe...(my guess is that their work just made an already-fragile part break...'shame they didn't give me a heads-up).

Drive around, have a friend stand along the road, and then "stop", and note if one or both wheels jerk backward...in my case, you'd see the front end shoot back about 2-3"...What a shock to see this! The lower control arms will run from $100 to $150 each, and you'll need to pop the balljoint (a good tool to do this is made by OTC...looks like a nutcracker)...Mine's an '05 S40, so things may be a little different on yours, but probably not too much.