2000 S70 GLT SE vibration

jmartin919 · Post by **jmartin919** » 13 Aug 2023, 07:12

What is the most likely cause of vibration in the brake pedal when I have it in drive and the brake is applied, like at a stop light?

Post by **scot850** » 13 Aug 2023, 08:56

If the car is at rest, then check the top torque rubber mount for splits, and the lower one under the middle front of the engine, but the usual main one for me is the engine mount under the RHS of the engine under the crankshaft pulley failing/separating.

Neil.

jmartin919 · Post by **jmartin919** » 13 Aug 2023, 16:09

The upper mount (broken) and rear hydraulic (leaking) mounts were recently replaced. The front mount seemed ok and the end mount too - it wasn't sagging and making contact with the frame. Could the torque mount do it? There is no vibration in neutral.

Post by **abscate** » 13 Aug 2023, 18:51

If they were replaced with off market or polyurethane type mounts you will feel more vibration than a Volvo mount , which are designed for damping and mounting

Post by **scot850** » 13 Aug 2023, 19:31

From what you are saying you replaced the rear lower mount and the upper torque mount, but left the lower torque mount, crank pulley engine mount and front hydraulic mount.

To check the crank pulley mount, you need to remove the RHF wheel and support the car on a axle stand. The use a floor jack with a piece of wood like a 12-18" x 1/2-1.0" thick between the jack and the oil pan at the RH end. Then use the jack until you just start to lift the engine and then check for separation between the rubber pad and the metal base it should be bonded to. Some of the mounts have metal tabs front and back which are there to prevent the mount actually shearing off should the bond fail. You can seldom tell that mount is bad just by looking at it.

Neil.

jmartin919 · Post by **jmartin919** » 13 Aug 2023, 19:58

The rear mount is Corteco and the upper is Pro Parts Sweden - no poly. I checked out the right side mount pretty well when I had the engine out in March. But you guys are pointing to the mounts as the most likely problem so I'll check them all.

Post by **scot850** » 13 Aug 2023, 23:36

For the problem you are describing, those are the most likely sources for the vibration. Pro Parts are not my favorite by a long shot, but was this problem there before you swapped the mounts?

If we eliminate these as likely issues, then we can look into this further for other possible sources.

Neil.

jmartin919 · Post by **jmartin919** » 19 Mar 2024, 12:42

Found the problem. When I lifted the drivetrain to reseal the trans valve body cover the rear mount fell out. The threaded stud on top of the mount broke clean across. Looks like a defective forge. The part is Corteco 9434435. Replaced with the same and vibration is greatly reduced.