Vibration at low speed w/mild acceleration
 

I have a 2005 XC90 V8 with 111k.. Last winter I heard a loud pop sound by the front driver's side wheel while turning slow in a parking lot that had patches of ice. As time went on I began to notice a low vibration while accelerating mildly, at low speed. The vibration would be more pronounced if accelerating mildly uphill. Now when I define this vibration, it's more like a wobbling feeling. The vibration would be felt around 1500-2000 rpm and at a speed of less than 35mph. If the vibration starts and I don't accelerate any harder, the vibration becomes aggressive until I let off the accelerator and the vibration stops. Now while accelerating normally at any speed or highway speed, I don't feel this vibration. However, while traveling 40 mph or higher, I do feel a brief vibration when there is a bump in the road.

So I decided to replace the front CV axles, lower control arms, ball joints, upper suspension parts, and outer tie rods. Prior to these replacement parts, the vehicle had new subframe bushings installed, trans flush, haldex fluid replacement. The problem still existed after the parts were replaced.

I did check the main axle shaft but I didn't notice anything loose. However, while using a pry bar on the driver's side front axle that enters the transmission there was a lot of lateral play; more than a 1/4". So is this lateral play the vibration I'm feeling. So to my question to any pros out there, can stress from the cv axle cause damage to inner transmission gear bearing, or is this vibration from something else?

Thanks.

I am always amazed at how much play there is on the driver's side axle where it snaps into the transmission. And not just on volvos either. Everything is like that. I don't see how it doesn't shake the car to pieces. That 1/4" sounds very normal to me.

Thanks for the info.

I'm having something like this, not quite the same, but similar. A little research pointed me in the direction of the lower engine mounts. My vibration seems to match the rpms... rpms go up, the vibrations goes up. sometimes it fades away almost completely, but as rpms change, it always comes back. Every once in a great while, the engine loses power as well, like 1% of the time, but comes right back. Vacuum leak crossed my mind, but I could never find it. In stumbling upon the lower engine mounts, I learned that they have vacuum hoses that plug into them. Why, I am not yet sure, but now that I know that, it makes perfect sense. Once the motor mount bushing deteriorated, the vacuum line plugged into it leaks periodically. Makes sense to me now that I know that. I have a place to look for my engine vibration and very occasional power loss. Hope this helps.

I have finalized the inspection. The vibration/shutter is caused by the torque converter. I plan on changing the trans fluid to see if I can temporary fix this issue. I had changed the fluid in late 2107 with Amsoil. However, after changing the fluid I began to notice shift flares, and now the shuttering. Can Amsoil be the culprit. I'll let you know..

I decided to change the fluid in late October 2018, using Mobile 3309. Its December 06, 2018, and here is my feedback. The shifting seems to be a lot more smoother and I hardly notice any shift flares from 2dnd to 3rd. The shutter seems to have minimized by at least 75%. I still have shutter, but you really need to control your acceleration to make it happen. I will give another post as time goes on. So in my opinion for those who want to change your trans fluid for this type of transmission, use Mobile 3309, and DO NOT USE AMSOIL. Amsoil may have some good products, but their signature series trans fluid seems to contain something that caused too much slippage. I had the same outcome on my Harley when using Amsoil primary fluid. It caused clutch slippage which was confirmed by two different independent dyno testings. When I called Amsoil about the issue, they asked if the engine had any upgrades, to which it did. The associate related their primary fluid is only for vehicles with no engine upgrades. What a crock of BS. Have a good holiday dudes.

It's March 20, 2019, and there is no longer have any shutter, or even shift flare for the past two months. The transmission operates great. So in my opinion, stay away from Amsoil and use Mobile 3309.

I have the exact same issue with my 2011 xc90 V8
did replacing the lower engine mounts fix the problem ?

The low vibration at low speed and low rpm that goes away once you speed up would mostly be caused by the torque converter slipping. I never replaced the engine mounts because they are ok.

The description of your issue is very similar to what I have been experiencing over the past 9 months. What was it that rectified the issue in the end? The change in transmission fluid?

I sold the vehicle. The shutter is due to the torque converter slipping, and it was quickly breaking down for me. The valve body was replaced years before the shift flare, but replacing the valve body may not fix the shift flare. Based on the mileage the trans needed to be rebuilt. This type of work requires the engine to be dropped in order to remove the trans. I have no shop, or the experience to work on the trans. The engine shaft seals was also leaking oil. I had to part ways and move on.

Thanks for the quick follow up!