zhandax
08-21-2010, 05:16 AM
I got to pay some stupid tax this week. I know motor mounts on German cars are a maintenance item, and need to be replaced at most by 150k miles. I replaced them on the departed E28, the W124, and even wondered how soon the new R129 would need them.
OK, maybe I am getting old. On the best car I have ever owned, that I drive to work every day (and usually push to 90mph at least once on the trip) it never even occurred to me. On the way in last week, at 80mph on two week old pavement it sounded like a pebble hit the undercarriage of the car. After that, it sounded and felt like I was driving in the rumble strip. I thought I had thrown a wheel weight. When I exited and got to the stop light, the car was vibrating up and down. So much for the wheel weight. It occurred to me to check for codes around lunch time and I tried to do that by memory (been a couple of years since the last stomp test). I stomped the pedal 5 times and turned on the key. This didn't work so I tried it again (a couple of times). When I started the car to clear the excess gas, the engine raced to redline. I shut it off and tried again with the same results. I popped the hood to be reminded the cowling prevents any viewing of the throttle cabling and when i restarted it, it did so and idled normally. During lunch I look here and get reminded that I need to turn they key first and afterward get a 1444. Logistics (could not get parts by the weekend, had to be at work the next day, and the R129 is jacked up in the garage for another project) dictated I take it to the indie. I find out the next day that a motor mount broke, and the engine racing had allowed the fan to hit the shroud, breaking both. It also stretched the upper rad hose and cracked the neck on my 3 year old radiator. On Monday, I find out that there was still a vibration and they were putting it back up to check. The trans mounts were shot as well. After all this is replaced and I pick it up, I am told that there is still a vibration between 20 and 50mph and they think it is the driveshaft. Since they are downtown, 50 may be as fast as they could get it. It is there until 80.
Sorry this is so lengthy, but if it helps someone else realize that they MUST change their motor mounts while it is relatively painless, maybe it is worth it.
Finally the question... I don't see the constant "gotta replace the driveshaft by xxx" like I did on the E28. Is this the most likely culprit or is there something else worth checking? For a little background: entire front suspension and all 4 struts replaced in last 2-3 years, front end alignment and all 4 tires balanced and rotated the week before this happened. The car does have a PS drip but other than that, drove flawlessly before this. If it does need a driveshaft, will I be OK driving for a few weeks before I can get some vacation to have it replaced?
OK, maybe I am getting old. On the best car I have ever owned, that I drive to work every day (and usually push to 90mph at least once on the trip) it never even occurred to me. On the way in last week, at 80mph on two week old pavement it sounded like a pebble hit the undercarriage of the car. After that, it sounded and felt like I was driving in the rumble strip. I thought I had thrown a wheel weight. When I exited and got to the stop light, the car was vibrating up and down. So much for the wheel weight. It occurred to me to check for codes around lunch time and I tried to do that by memory (been a couple of years since the last stomp test). I stomped the pedal 5 times and turned on the key. This didn't work so I tried it again (a couple of times). When I started the car to clear the excess gas, the engine raced to redline. I shut it off and tried again with the same results. I popped the hood to be reminded the cowling prevents any viewing of the throttle cabling and when i restarted it, it did so and idled normally. During lunch I look here and get reminded that I need to turn they key first and afterward get a 1444. Logistics (could not get parts by the weekend, had to be at work the next day, and the R129 is jacked up in the garage for another project) dictated I take it to the indie. I find out the next day that a motor mount broke, and the engine racing had allowed the fan to hit the shroud, breaking both. It also stretched the upper rad hose and cracked the neck on my 3 year old radiator. On Monday, I find out that there was still a vibration and they were putting it back up to check. The trans mounts were shot as well. After all this is replaced and I pick it up, I am told that there is still a vibration between 20 and 50mph and they think it is the driveshaft. Since they are downtown, 50 may be as fast as they could get it. It is there until 80.
Sorry this is so lengthy, but if it helps someone else realize that they MUST change their motor mounts while it is relatively painless, maybe it is worth it.
Finally the question... I don't see the constant "gotta replace the driveshaft by xxx" like I did on the E28. Is this the most likely culprit or is there something else worth checking? For a little background: entire front suspension and all 4 struts replaced in last 2-3 years, front end alignment and all 4 tires balanced and rotated the week before this happened. The car does have a PS drip but other than that, drove flawlessly before this. If it does need a driveshaft, will I be OK driving for a few weeks before I can get some vacation to have it replaced?