1998 Subaru legacy AWD question.

[NJC]

My parents recently bought a 1998 Subaru legacy AWD.

I took it for a drive yesterday and noticed it has quite a bit of drag - IE when foot is off the gas the car slows down quickly and does not coast easily.

I don't know actual gas mileage numbers for this car but I know it's not great. Is this "drag" just a function of AWD?

 

[Gurkha]

The Legacy is prone to stuck hand brakes, happened to someone I knew, she drove the car for miles like that till the engine overheated, the AWD should cause no apparent and detectable drag. Get your hand brakes checked, also if it is equipped with the hill holder clutch, it is probably faulty.

Also check if the AWD system oil as well as front transmission and rear diff oils have been changed, if they are old, they can sludge up and cause drag as well.

 

[Eddie]

My 2000 Subaru just rolls and rolls when I let of the gas or shift into nutral. Sounds like something is wrong. Check for brake drag, tire pressure

 

[oilyriser]

Pump up the tires. Try pushing the car, with the transmission in N, and see if one person can make it move.

There *is* more drag on AWD than a FWD car, since it has an extra differential in the back, and the rear wheels don't turn freely like on a FWD. My car slows down faster than FWD cars behind me, even when I coast in neutral.

I changed the rear axle gear oil in my Subaru from 80w90 to Amsoil Series 2000 75w90, which should have reduced the drag a bit in cooler weather. Unfortunately, this oil is discontinued, and all their others are 50% thicker at 40C. Redline 75W90NS has similar numbers to the old Amsoil stuff, though. Mobil 1 75w90 might be another choice. I'm actually thinking of trying Redline 75w80 in the rear, since I never go offroading in summer, and the oil will be thick enough in winter when I need it.

 

[NJC]

quote:

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Originally posted by oilyriser:
Pump up the tires. Try pushing the car, with the transmission in N, and see if one person can make it move.

There *is* more drag on AWD than a FWD car, since it has an extra differential in the back, and the rear wheels don't turn freely like on a FWD. My car slows down faster than FWD cars behind me, even when I coast in neutral.

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I did suspect it would have more drag but it seems excessive.

Actually I had to push it a few feet in my garage and it was very hard to push.

I'll ask him to have a look to see if the e-brake cables are stuck or if any of the calipers are dragging.

 

[oilyriser]

Try putting it in N, while coasting to a red light.

Some of the earlier models had weird programming in the transmission control that would keep it in 3rd gear for a long time, if you happened to be climbing hills a lot. There would be a lot of engine braking when you let off the gas. Maybe it's hanging in 3rd longer than you expect. Is the transmission shifting properly?