Ok, I bought a 95 850 wagon with a manual trans, 159k. Car seems to be in very good shape owner has most of the stamps in the maintenance book, overall condition seems good. Was a MA car, so it does have some corrosion and a little rust, but mechanically seems solid.

Just a few issues...

Above 25mph+ there is a loud humming noise - I thought it was just poor tires at first, but now I'm thinking wheel bearings. It's loudest between 35-55.

A slight rattle at low rpm in 1st and 2nd gear - under 2000 rpms - exhaust shield?

Last one, but hardest to figure - a knock/thunk noise in most gears at speeds 20mph-70mph. It does it every 20-60 seconds and a slight hesitation occurs after it. Only does it in gear and doesn't do it above 70. Not a clue on this one. Drove back from Boston to VA, over 600 miles, didn't start happening until about the last 70 miles.

Thanks in advance!

 

1. Sounds like a wheel bearing
2. Possible heat shield or the one on the steering rack.
3. Is it possible it needs a tune up and is misfiring under load?

 

On #3 it might be possible. It seems like all maintenance was done according to the book, but I don't have itemized receipts.

Took it to the mechanic today - we'll see what they say.

 

So what did they say?

 

#1 Was tough to isolate - not wheel bearing, not tires, thought it might be a transmission bearing of some sort?

#2 Heat shield, but apparently on 850s it's one giant one that's nearly impossible to mess with? There was an exhaust bracket that needed to be welded - rust.

#3 wasn't able to duplicate the problem

It needed some basic stuff that I already knew about, fuel filter, oil change. He said it's rustier than it looks on the surface but seems like a solid car for now.

May take it to a local volvo expert. Trying to avoid the dealer for cost reasons.

 

1. Maybe the bearing in the right side axle is bad.

2. You can mess with them and adjust on them some.

3. Hopefully you can get it to act up again.