98 V70 AWD rear driveshaft and sway bar

Post by **holler1** » 30 Aug 2008, 20:24

I was checking rear brakes a few days ago and noticed these problems in the rear underside of the car. 1-The rear end appears to be leaking around the left drive shaft. 2-Also the rear sway bar is rusted pretty badly. Is the leak likely to be a grease seal at the drive shaft? Is this repair similar to front drive shafts? I think I read all the repair links and didn't see anything about rear sway bars (if that is what it is). Any thoughts?

Post by **MadeInJapan** » 30 Aug 2008, 20:44

That rear sway bar looks pretty narly- already rusted apart from the frame so it's toast and isn't going it's job. I'm surprised you haven't heard it clanking around. The rear differential really needs to be rebuilt but how to go about that I'm not sure. Hopefully those who know about this will chime in. I do know that the oil back there can and should be replaced (although Volvo will probably tell you it doesn't need it). It's a good thing you caught it early before it started giving you fits- certainly a weak link in the early AWD systems.

Post by **JRL** » 30 Aug 2008, 21:16

MadeInJapan wrote:That rear sway bar looks pretty narly- already rusted apart from the frame so it's toast and isn't going it's job. I'm surprised you haven't heard it clanking around. The rear differential really needs to be rebuilt but how to go about that I'm not sure. Hopefully those who know about this will chime in. I do know that the oil back there can and should be replaced (although Volvo will probably tell you it doesn't need it). It's a good thing you caught it early before it started giving you fits- certainly a weak link in the early AWD systems.

Expensive any way you do it.
Buy a used rear from .www.erievovo.com , this will probably be your best way but will still be very expensive

chucksrt · Post by **chucksrt** » 31 Aug 2008, 11:17

i am just relearning volvos after a long break but are the rear axle seals non replaceable in the diff?

Post by **holler1** » 31 Aug 2008, 21:13

Thanks, gentlemen. This reminds me a little of a recent prostate exam (Doctor, how bad is it?). Luckily that turned out OK so far. I waited a day before reading JRL's message because I didn't want to hear the bad news. I had done work on the PCV, just bought $600 worth of tires, and mentally committed myself to fixing up the front suspension, which is not in bad shape. I was confident I could do the front end OK with time. However, now I have to consider whether it makes sense to put much more money into a car that at best may be worth $3000-4000 and probably much less as it sits. Also, I'm a little daunted by working on this complicated rear end myself. I guess I'll price it at Erie before deciding. In any case, thanks for the help.

I love driving the Volvo, but it sure hasn't lasted like my 91 Camry that has had only one unscheduled repair in 160,000 miles. I had to sell back my 98 Tacoma to Toyota in their buyback program because of a rust problem, otherwise I might give up the Volvo and stick to the truck. Oh well, thanks again.

Post by **MadeInJapan** » 31 Aug 2008, 21:36

Don't give up yet.

I'm searching for your answer now and getting quite an education. Will share what I find in a bit.

chucksrt · Post by **chucksrt** » 31 Aug 2008, 21:43

So is it easy to say that the rear diff axle seals are not just as simple as pulling the axle shaft popping one seal out and installing a new one? Just curious?

Post by **MadeInJapan** » 31 Aug 2008, 21:48

I had posted a lot of info and then deleted it. Apparently I was dealing with the front...you're wanting information for the rear. I'm still checking.

chucksrt · Post by **chucksrt** » 31 Aug 2008, 22:10

it looks similar to a front axle, in that it is not a solid rear axle, it has C.V. joints going into it I know that most C.V.axle shafts are just held in by a snap ring able to be pried from the case with pry bars and some have c-type retaining clips that requir the rear axle center section cover to be removed and the clips removed before the axle can be removed from the housing (i've only ever seen the compressable snap ring type) not sure how volvo is? sorry for long winded questions I am just trying to get as much info on these cars as i can so if down the road I run into a problem such as this I can do it the best/cost effective way I know how
Chuck

Post by **MadeInJapan** » 31 Aug 2008, 22:25

Well, I'm reading a ton and learning because I don't own an AWD Volvo and know very little about their drive shaft, etc. system. From what I've read there's no one really replaces the internal parts of the rear differential (called the "final drive") and it doesn't even have a real gasket. Like other engine/transmission parts, it does have a chemical (anaerobic gasket that is rolled on) gasket that holds it and a cover on from the rear (opposite side of where the propeller shaft enters). It could be that this is the only place that is leaking or the seal from the propeller shaft that enters it. If it's not making noise, that's a good sign but you still need to figure out where it is exactly that is leaking. If you have to split the final drive it has to come out of the car to do that and then put it back together- so there's a whole lot of labor involved. This piece also has no real drain plug so to change the oil out of it you have to use a vac unit (like a mighty vac). VADIS only list replacement units for it... Currently I'm looking for torque values for the flange nuts that hold it together. It could be that these have loosened up and retorquing them would solve your leaking issue. Either way, I would look at pulling out the fluid in there and replacing it.

Here is a diagram of your rear gear box: