2004 V70 2.4 idle vibration in-gear

[krhodes1]

I'm in the process of sorting out my recently acquired 2004 V70 2.4 automatic, 120K miles. It's a pretty typical car that is at the "mid-life crisis" stage where lots of maintenance needs to be done. But overall it is in very nice condition and has been well kept. Bonus - it has spent it's entire life in Naples Florida - it has no idea what road salt is. Everything underneath is SHINY. And the roads here are smooth as a baby's bottom compared to up north. My 14th Volvo, but my first FWD Volvo.

So with the background explained, here is my issue. I have DIY replaced all seven motor mounts, and the front control arms and balljoints. This has made a MASSIVE improvement in how the car drives. It had some fairly epic vibration and clunking and banging going on. Before doing the motor mounts, even in neutral it rattled the dash. Now it is just about perfectly smooth in neutral. But there is still what seems like substantial vibration and "boom" when idling in gear and stopped. It goes away as soon as I start moving a bit, but it's pretty annoying - especially with FL 5-minute traffic light cycles. Doing lots of reading, the subframe bushings COULD be an issue, but I don't seem to have any of the other symptoms of them being bad. From what I can see of them without taking the bolts and plates out they look "OK". They do seem VERY hard - I am sure the FL heat has baked them to a fine crisp.

So will replacing them make a big difference in this case? I haven't driven another one of these cars in many years, so I don't know what normal is for them. I have had a couple of Saab 9-5s that are notorious for this stopped in gear vibration, this car seems on par with them. But I don't recall that being a big complaint with P2 Volvos the way it is with the 4cyl Saabs. Replacing them doesn't look to be much fun, though not worse than what I have already done.

All thoughts appreciated!

Pretty car:

pax side by kevinr1916, on Flickr

-Kevin

[Blacklab467]

I recently replace mine after having changed the whole front end. It made a substantial difference. One thing you can do is take the plate off, stick a screwdriver or pryer in the bore and see how much it moves around and assess it from there. My car had 280,000 kms on it and it's an '03.
The job itself is pretty easy and straightforward, I've attached the link to my tutorial below. The Volvo brand subframe bushings are less than $ 40 each, don't use aftermarket parts. Should take you 3 hours or less with hand tools, no special tools are required.
Beautiful car by the way! I hope those other parts you put in it were genuine Volvo also, I learned my lesson on aftermarket parts and got to replace my front end twice last year!

viewtopic.php?f=9&t=96106&p=563280#p563280

[Blacklab467]

I should add that these 5 cylinder engines have a natural vibration in the 725 RPM range that you will be unsuccessful at dampening. I would describe it as a 4 cylinder diesel vibration, and it goes away at about 750 RPM and above. I don't know what the "boom" you're talking about might be? Maybe you can record it or attach an iPhone video so we can better understand it.
One other thing, make sure to change the large bolts if you do decide to change the subframe bushings, they are 1 time use only, even if they appear to be in good condition, plus they're only about 4 bucks.

[krhodes1]

Thanks! I have Volvo bushings on order from IPD - backordered a bit, but supposed to ship to me the beginning of the week. The motor mounts are all oem Hutchinson, amusing that you can see where they ground the "Volvo" off of them. Control arms and balljoints are IPD's heavy-duty parts - I have no desire to do that job again either. I do have new bolts. So I will have at it when they get here.

"Boom" is bass vibration being transmitted into the car. Literally if I let the car just creep forward it goes away. I don't have an iPhone, I doubt my Motorola would do a decent job of recording it, but worth a shot.

-Kevin

[krhodes1]

Did the subframe bushings today. Went smoothly, only took 1.5hrs to do them. Helped the in-gear idle vibration quite a bit. I have to think it's as good as it is going to get. Made a noticable difference in feel while driving too - sharp impacts are tamed quite a bit - we have tons of reflectors in the roads here - hitting them is much smoother now.

-Kevin