New to Forum. Need some asistance w/AWD on 98 XC, please

KnightAB · Post by **KnightAB** » 16 Apr 2012, 22:50

Hi Folks!

I just registered and I am glad to join the group.

I have a 1998 V70 XC AWD with 264k miles that seems to be burning up (at least getting hot) the oil in the transfer case. My transfer case went out about a year ago and I got a used one from Tom's Foreign Autoparts that was in very good condition. I have run all the same tires since replacing it, and it's been working fine but lately I have started smelling hot oil on and off. I had my mechanic (not a volvo tech but a very good general mechanic) check the fluid and he said it did smell a bit burned, and fluid was a level was a bit low so he topped it off. But the box does not seem to be leaking.

I also hear the transfer case whiring when I drive now, like it's noisier than it used to be, since I never used to hear it while i drive. But it's not grinding.

My questions are 1) Does anyone have experience with these, and any maintenance suggestions on what to do/check so i can prevent the transfer case from failing? 2) I'm considering putting Prolong super lubricant heavy duty gear oil in the transfer case - any reason I shouldn't do that? (I've used prolong in my engines for about 10 years and never any troubles and it seems to help). 3) Does anyone have experience/suggestions about just disconnecting the transfer case and removing the propeller? If the transfer case fails again I'd rather disconnect it then fork out $1000 for another one.

Thanks for your time and attention!

Post by **vjaneczko** » 18 Apr 2012, 10:25

welcome to the forum!

There's a few who have disconnected the shaft so you're a FWD car.

Do you have the correct type of fluid in the case?

KnightAB · Post by **KnightAB** » 19 Apr 2012, 15:41

Hi, thanks for the reply!

Yes, my mechanic checked the fluid and I believe it's 90w, but I'd have to double check.

Do you have any feedback on if it's a simple thing to disconnect the propeller?

thank you

Post by **jimmy57** » 19 Apr 2012, 15:54

All that needs to be done is undo the 6 allen cap screws at front and rear CV joints and then undo the two bolts holding center support bearing on the crossmember and slip the shaft out.
When tires are the same size the other issue is the viscous coupling getting stiff.
Pull the driveshaft to prevent any damage for now.
I have an idea on getting the viscous coupling stiffening repaired that I will have time to sort out soon. I will then share the process on here if it is successful. New VC's are expensive and any you find used are likely as bad or nearing to be as bad as what you have.
The angle gear (transfer case) can have a hole drilled for a small bolt on the bottom of sump. With that the fluid can be drained and refilled, maybe at every oil change for 3 changes, to get the fouled fluid flushed out.

Post by **matthew1** » 19 Apr 2012, 16:23

What Jimmy said. Here's an AWD propshaft removal search result.

KnightAB · Post by **KnightAB** » 21 Apr 2012, 16:43

Dear Jimmy and Matt, thanks for the replies. And thanks so much for the search link - I gues I wasn't phrasing my search correctly. I'll try some of the fixes before retiring the propeller. Thanks again!

Post by **BEJinFbk** » 21 Apr 2012, 17:07

Matched tires?
Just checking.

KnightAB · Post by **KnightAB** » 22 Apr 2012, 00:03

Hi BEJinFbk, yes, the tires are matched. Thanks for checking.

When I first had trouble with the bevel gear, the first time 2 years ago, I did reseach and found out about the matching tires issue. I had occasionally run mismatched tires before then, but all matched as long as I've had the current bevel gear. Thanks!

twncty · Post by **twncty** » 22 Apr 2012, 10:17

I had an issue with the sleeve that connects the transmission to the transfer case. Since the sleeve is made of a different metal it will stip over time. Do to the stipping it chewed away at the gear spindle of the transfer case. Make a long story short I disconnected the drive shaft. Pretty simple process with great step-by-step directions on this site.

KnightAB · Post by **KnightAB** » 14 May 2012, 02:29

Thanks twncty, I'll look at the instructions.