Hard thump from gears coming down high speed to halt (2008 C30 T5 136k miles)

Mikele82 · Post by **Mikele82** » 24 Aug 2020, 13:51

Hello,
sometimes after a fast highway drive, when i reach lower speed 30mph and then come to a stop speed, there is a hard "thump" or maybe a "kick" feeling (not a sound). and then when accelerating from stop to move there is a second stump ...
this can be sometimes not happen if accelerating very slowly... and it dissapears most of the time.
any idea what would be a more technical term and diagnostic to this ?

Should i try a drain n fill ?
file:///C:/Users/Mikele/Downloads/S40%20'04%20Tranny%20Flush.pdf
was suggested here that its similer to C30
viewtopic.php?f=25&t=18361&p=76981&hili ... ick#p76981

(2008 C30 T5 136,000 miles automatic)

Post by **theWIFES_S70** » 13 Sep 2020, 16:51

Engine mounts?

roblamar · Post by **roblamar** » 24 Sep 2020, 14:19

In my V50 (2005 120kmi), this happens pretty consistently around 18MPH. It seems much worse when it's hot (both ambient and engine temperatures). Slow deceleration makes it sound less bad, but it usually doesn't go away entirely. Oh! And if I'm doing manual shifting, it does not shift at 18MPH, but rather at the time I downshift.

I have tried a number of things to resolve this since I bought the car 12 months ago. A drain and fill was pretty easy, but did not help in my case. (Although I've seen lots of positive reports on the web.) I've been planning to try replacing the motor mounts, and the car recently blew its head gasket, so it seems like a perfect time to swap the mounts out. I'll try to remember to come back here and report on whether it makes a difference.

Post by **MoVolvos** » 24 Sep 2020, 17:46

theWIFES_S70 wrote: ↑13 Sep 2020, 16:51
Engine mounts?

Should do a flush first assuming his is an auto by the link he provided. Symptoms not likely in a manual as our 08 C30 T5 2.0 6 Speed has about the same mileage.

.

Post by **theWIFES_S70** » 01 Oct 2020, 07:38

I think Volvo mounts are designed to cradle our engines cradled in ways Toyotas and Honda don't. Which in large part determines why we like the feel of our cars! (Having replaced Volvo, toyota, Nissan, and Honda mounts... the Swedes do it a whole other way!) There are four mounts to check out... I bet one is shot...