AWD System

Wammer · Post by **Wammer** » 25 Mar 2009, 08:57

Just curious - I've done some digging and heard horror stories of big repair bills on the older AWD system if tires are slightly different diameters, etc. I have a 2002 xc70 and from what I can tell, it has the 2nd generation Haldex system, which, again, from what I can tell, is supposedly more resistant to minor differences/issues in the tires. Is there any way to verify which system I have, and if it is the 2nd gen., what is the real world reliability of said system?

Lot of questions, not urgent, just curious. I figure it's better to inform myself now, than to pay later. Cheers, Greg

Post by **JRL** » 25 Mar 2009, 16:02

You do NOT have the Haldex, you have the 1st Gen, viscous coupling AWD system, the one that can be very expensive to repair... now what's your question?????

2003 was the 1st year for the Haldex in V70XC's 2002 S60 AWD's have Haldex, but the wagon's Haldex came a year later,
sorry!

Wammer · Post by **Wammer** » 25 Mar 2009, 20:58

That answered my first question - which system I have. Unfortunately, it wasn't the answer I wanted to hear. I'll be careful w/the tires, I guess. Thanks.

Post by **JRL** » 26 Mar 2009, 05:22

Your GUESS?

Let me make this clear, I've seen a bevel gear go south after someone rode on the (donut) spare for 100 miles!

slc10844 · Post by **slc10844** » 27 Mar 2009, 15:15

Can the 1st gen system be replaced with the Haldex unit?

Post by **JRL** » 27 Mar 2009, 16:30

since you obviously know nothing about cars, I suggest you do some reading, a LOT of reading
and the answer is, of course, no

slc10844 · Post by **slc10844** » 28 Mar 2009, 06:34

Thank you for your ignorant answer. I have been a mechanic for over 40 years working mostly on domestic light trucks and cars. I think I know a little about cars. A simple "no" would have been sufficient. The added remark was unnecessary. Thank you for your response.

Post by **MadeInJapan** » 28 Mar 2009, 06:57

I agree with your response...simple "no" would have sufficed.
Anyway, I hope you figure things out on your AWD system.
Remember, they are sensitive, as you know- don't use that donut tire- replace it with a real size spare when you get the chance.

billr99 · Post by **billr99** » 28 Mar 2009, 16:34

It looks to me that, like the transmission, the bevel gear is a bogeyman if the car has been properly maintained. Folks who put the boot to the car on slippery surfaces or otherwise mis-treat the driveline have problems. Failure to change out the lube at a reasonable interval probably doesn't help much either. Is it a weak point? Well, it does not seem to be up to typical Volvo standard but is the thing going to fail just because you drive the car a few miles? Doesn't seem plausible if the car is used according to instructions. As an example, these stories of a failed gear because of using the spare, I have to ask if the spare was properly inflated, etc. These days most folks are morons when it comes to the spare. Obviously, if they ran the donut for 100 miles on an underinflated spare they can't be too with it since they aren't supposed to be used for that distance anyway. So again, these failures seem to indicated misuse by uninformed users.

Anyway, I am just about ready to turn over 170K kms (105K miles) and my bevel gear and transmission are fine. I also know a fair number of folks in the same boat. But we all maintain the car too. So I say maintain the car to the book (with the exception of actually changing your driveline lubes) and enjoy the ride. On the other hand, if you treat the car like most people treat their Chevs or Fords, you might have some issues. Of course, the whole idea of whether cars should be maintained or not and how Japanese cars seem to defy the principles of wear and tear is a whole other conversation.

Cheers,

Bill

Post by **MadeInJapan** » 28 Mar 2009, 16:48

billr99 wrote: These days most folks are morons when it comes to the spare. Obviously, if they ran the donut for 100 miles on an underinflated spare they can't be too with it since they aren't supposed to be used for that distance anyway. So again, these failures seem to indicated misuse by uninformed users.
Bill

Hey Bill...nice to have you aboard- the 1st generation bevel gear is prone to failure even if the spare is not under inflated and you drive on it more than the prescribed 50 miles. An example would be someone who uses it for 40 miles...still doesn't have the tire that went flat repaired, so drive on it another 40 miles then next day, etc. In Europe the spare is not a donut- go figure. Volvo says that driving with more than 2/32 of an inch difference between the two tires on the same axle can cause damage. So, like I said before- it's best to change out the spare for a real tire when you get a chance. All of my cars have full-size spares even though I don't have AWD in any of them.