2006 XC90 2.5 FWD-front drivers side growl

aaron1611 · Post by **aaron1611** » 15 Mar 2019, 12:00

SO, I've jut purchased an 2006 XC90 2.5 FWD as an upgrade to my V70 that we are giving my son and I've got a growling under acceleration going straight that disappears around 35 mph. Almost at first sounds like a small exhaust manifold leak but when the car is in neutral I cannot duplicate the sound. I put the front up on blocks, put it in neutral and could spin the front wheel with no sounds. I was hoping it was the wheel bearings but can this be ruled out by my test? Above 35mph no noise. Doesn't change at all whenever I'm turning in either direction. Sitting in D and putting the brakes on and trying to move forward or reverse with brake all the way depressed I think I hear what could be the same sound but it's just at a different octive, a bit higher and not as throaty. More like creaking which may be normal. Could this all point to a wheel bearing? The vehicle has been well maintained at the dealership by PO with most recent maintenance being the full 120K where they replaced the timing belt. Records since then are simple oil/filter changes per Carfax report. Doesn't seem to affect drivability yet but I'd like to pre-empt an expensive repair.

Post by **RickHaleParker** » 15 Mar 2019, 14:46

Is it a clicking noise or a growl?

The spines on the end of the drive shaft working against the spines in the hub can produces a clicking sound that rolls like a growl. This is harmless.

The remedy is to coat the union with semi permanent Loctite (Blue). Most mechanics don't do this unless the customer wants it done because, disassembling a union doped with Loctite requires heating it up with a torch.

aaron1611 · Post by **aaron1611** » 15 Mar 2019, 16:18

not clicking but I just drove my wife's 05 xc90 with 230xxx and hers makes a similar sound but not as loud. I wonder if it's just the engine/turbo and age being just a tad bit loud upon acceleration from a stop? The V70 doesn't make any noise. I've actually not heard this type of low growl before in a Volvo. It could all be normal I guess. Interesting though.

Post by **SuperHerman** » 15 Mar 2019, 16:58

Look at the heat shields from the engine bay all the way back. Check your motor mounts, I think it has five.

As for a wheel bearing, it does not sound like one based on your description. That said, I had a wheel bearing growl on mine that passed every test - after replacing everything - I mean everything including the transmission - the last thing left was the wheel bearings. Upon replacement the sound was gone.

aaron1611 · Post by **aaron1611** » 15 Mar 2019, 20:58

not clicking, almost like there is gravel in it, which may be the biggest tell. When I accelerate into a turn from a standstill I can feel a slight vibration in the steering wheel. Is there another way to confirm wheel bearing? I've looked at the top torque mounts/engine mounts and though they are a bit loose, similar to my wife's volvo, but I'm not convinced they are the culprit. I replaced all 5 on my V70 with little difference when all was said and done. Do not want to just throw parts at this just yet.

Post by **RickHaleParker** » 15 Mar 2019, 21:07

When you had the tire off the ground, did grab the tire at the top and bottom, then check for play?

Post by **mrbrian200** » 16 Mar 2019, 09:37

Something to consider. Rear wheel bearings on the P2 XC90s can manifest as a 'growl/groan' that transfers through the chassis and sounds like it's coming from the opposite corner: sound seems to be coming from the front left could be the front left or the right rear wheel bearing, etc.
May or may not apply to your problem, but it is somewhat important to know so that you are aware that noise that seems to be coming from up front may actually be due to a problem in the back somewhere.

aaron1611 · Post by **aaron1611** » 16 Mar 2019, 17:02

I actually didn't try to move tire top to bottom to look for play. Good call. I've read elsewhere that it can be deceiving to think it's gotta be the front so I will check the rear as well. I'll check it out tomorrow morning when I'm doing the oil change. Thank you for the input. Gotta say though that I love these trucks, Volvo's particularly. I just wish our two models had the 3rd row but you buy what you can when the price is right. I'd say that $1300 for a well dealer maintained xc90 with 175K is a pretty good buy. Ran vida dice and cleaned up all the codes and it's a great daily driver.

Nicodemus0 · Post by **Nicodemus0** » 16 Mar 2019, 20:53

I'm going to second SuperHerman's suggestion of motor mounts. I have the same car ('06 2.5T, but AWD - 150k miles) and had almost identical symptoms last year. Also was worried about wheel bearings, but didn't make sense since the grinding noice seemed to abate after a few seconds of acceleration and it wasn't related to speed. Our indy mechanic suspected motor mount issues. Upon inspection, one was clearly failed, which he replaced. The noice/vibrations were not as loud, but still quite evident. Based on that, I had him replace the others also. Mechanic said no obvious faults were evident in the others even after they were out, but once replaced, the sounds disappeared.

aaron1611 · Post by **aaron1611** » 17 Mar 2019, 14:15

Ok, no play top to bottom on either front wheels but play side to side. No noise rear wheels. Looks as if both bottom motor mounts have been replaced as they “look” new. Certainly no signs of failure that I could see. Top center mount has failed and will replace all 3 top ones and post back. Thanks again for the response.