Haldex 3 fluid/filter change on '05 XC70--Is it worth the trouble/cost?

kcb203 · Post by **kcb203** » 05 Jan 2018, 08:04

I've got an 05 XC70 with 109,000 miles. It's now our third car, which means I use it to haul around dirty dogs and bikes, and my wife takes it 3 miles RT 5x week to work to a tight parking lot where door dings are common.

I'm trying to keep it going for several more years. I've recently replaced the RF control arm, RF bearing, RF axle, thermostat (leaking), top engine mount and bottom right engine mount. I thought I had a major oil leak, but I think it was just the oil cap gasket (knock on wood--a UV test so far isn't showing any more leaking oil since I replaced it). I've replaced the power steering fluid, coolant, rear differential oil, and front angle gear oil. I plan on doing a Gibbons change on the ATF, replacing the tie rods, brake fluid, and fuel filter. The angle gear has a slow leak, but I'd rather just top it off every once in a while than pay $1,000 to have it resealed.

I'm torn about whether to try to replace the filter and fluid on the Haldex 3. (I'm pretty sure it's the Haldex 3 version--the filter cap is to the upper left of the unit around the 11 o'clock position.) I've seen differing opinions on whether it can be done without removing the prop shaft. I think that's more trouble than I want to put into it, and more expensive than I'm willing to pay someone else to do. But if I can do it without removing the shaft, I'll try it. What happens if the Haldex fails? If I'm stuck with a FWD car, I'm fine with that.

To summarize, I don't want to try to change the fluid and filter if halfway through I figure out that I can't finish the job without dropping the exhaust and removing the prop shaft. And if I don't do any preventive maintenance and it fails, what's the downside? Am I left with an undriveable car or just a FWD car?

Post by **vtl** » 05 Jan 2018, 11:30

Just FWD. Bad FWD, since the car still thinks it is AWD and it does not limit torque when needed.

Dropping one end of exhaust and the shaft and removing flange is easier in my opinion then working those two bolts out of the filter's cap, but I did that before a few times and I have tools. What is worse, your AOC pump will fail soon due to age, if not done so already. I'd wait for AOC to die completely and then replace filter along with the pump. Fresh fluid won't save the pump, it goes away mechanically (worn brushes, corrosion, leaking seal lets oil to come and destroy electric part of the pump).

kcb203 · Post by **kcb203** » 05 Jan 2018, 12:26

How will I know if AWD fails? Will I get an error message or CEL? I rarely--if ever--drive in situations where AWD is necessary so I don't think I'd be able to tell by driving.

Post by **vtl** » 05 Jan 2018, 12:39

Put front wheels only on snow, sand or dirt, push the pedal harder than usual. Should not slip. Or plug in DiCE and read the codes in VIDA. DEM-0006/7 - Haldex is dead.

Post by **abscate** » 05 Jan 2018, 15:27

We sent you snow to VA just to test this kcb203....

you are welcome.

Post by **E Showell** » 11 May 2019, 04:56

AOC-- Alexandra Ocasio Cortez?

Post by **vtl** » 11 May 2019, 06:43

Active on demand coupling.