Problem. Wheel hop when turning.

[The_Wizard]

I've done lots of searching and haven't been able to find anything about this. I have been frequently noticing wheel hop when taking 90 degree turns into parking spaces. The front tires seem to be gripping and skipping on the pavement. It pretty much only happens after highway driving for a while when the car is good and hot. This is the same type of thing that you would expect from a 4WD truck on dry pavement but the AWD shouldn't have this problem. Has anyone else experienced this? Is it a problem with the diff? I'm driving an '03 stock WRX wagon. Thanks for the help.

[REXme]

This would be the second thread I bring back from the dead. This Wizard wasn't kidding, there is next to nothing out there about the WRX shuddering and hopping around corners. I plan on changing the transmission and diff fluid to try and see if it will fix the issue, is there anything else I can do that wont cost me thousands of dollars?

If anyone can answer the question I would be grateful.

[Trainrex]

It sounds like the center diff is locked up. Great for snow, but bad for parking. Also hell on the rest of the drivetrain.

[MainFrame]

It sounds like the center diff is locked up. Great for snow, but bad for parking. Also hell on the rest of the drivetrain.

+1 center diff problems


Have you rotated the tires at least every 5,000 miles since the car was new? Uneven tread depths can cause the center diff to wear out prematurely, which will in turn cause the symptoms you are describing.

[REXme]

Yeah, thats kinda what I was thinking, although keep in mind that it only happens after driving long distances. If I start the car up in the morning and take it around the block, by the time I get back I am still able to park without any issues, however if I drive my 30miles to work I cant bare trying to pull into a spot.

As a small test I want to try an change my diff and trans fluid to see if there is any improvement. How do I go about changing the center diff fluid?

[Trainrex]

Yeah, thats kinda what I was thinking, although keep in mind that it only happens after driving long distances. If I start the car up in the morning and take it around the block, by the time I get back I am still able to park without any issues, however if I drive my 30miles to work I cant bare trying to pull into a spot.

As a small test I want to try an change my diff and trans fluid to see if there is any improvement. How do I go about changing the center diff fluid?

The center diff, gear set and front diff are all encased in the transmission and share the same fluid.

[REXme]

The center diff, gear set and front diff are all encased in the transmission and share the same fluid.

Yeah, I realized that on my way home with the fluid. I lowered my head in shame.....however, I still plan on changing the fluids, i checked my transmission fluid and I think it was low, but I'm not entirely sure. The other issue is that I don't know what kind of fluid is in there now, and I found out that WRX owners don't like using M1 full synthetic, so I'm not entirely sure what to do....

[jd92677]

Yeah, I realized that on my way home with the fluid. I lowered my head in shame.....however, I still plan on changing the fluids, i checked my transmission fluid and I think it was low, but I'm not entirely sure. The other issue is that I don't know what kind of fluid is in there now, and I found out that WRX owners don't like using M1 full synthetic, so I'm not entirely sure what to do....

Subaru extra-s fluid Subaru 75W90 Extra-S Gear & Transmission Fluid I believe this will work for you and comes highly recommended

[Trainrex]

Yeah, I realized that on my way home with the fluid. I lowered my head in shame.....however, I still plan on changing the fluids, i checked my transmission fluid and I think it was low, but I'm not entirely sure. The other issue is that I don't know what kind of fluid is in there now, and I found out that WRX owners don't like using M1 full synthetic, so I'm not entirely sure what to do....

Many will argue with my view on WRX gear oil, but I am a stout advocate for simple 75w90 dino oil. I tried it all. M1, cocktails, redline, royal sludge, etc etc. IMO, nothing beats good 'ol dino oil in a WRX unit.

There is always a give and take. While some of the cocktails and synthetic offerings may mask an inherent synchro problem, the diffs don't like them. The dino oil won't mask the synchro problems, but will protect the trans and diffs. As much as I like M1, it is literally the worse you can put in there. M1 was coming out burnt after 5-7k miles in the WRX's I was working on.

[REXme]

Many will argue with my view on WRX gear oil, but I am a stout advocate for simple 75w90 dino oil. I tried it all. M1, cocktails, redline, royal sludge, etc etc. IMO, nothing beats good 'ol dino oil in a WRX unit.

There is always a give and take. While some of the cocktails and synthetic offerings may mask an inherent synchro problem, the diffs don't like them. The dino oil won't mask the synchro problems, but will protect the trans and diffs. As much as I like M1, it is literally the worse you can put in there. M1 was coming out burnt after 5-7k miles in the WRX's I was working on.

If I can get dino oil from an auto parts store I will, but failing that I think im going to return the M1 i bought from Auto zone and I'm going to pick up some Vavoline, I have been using it on my engine ever since I got a new one installed and it seems to be a favorite in many of the how to's for changing diff fluid. I am really hoping that by spending $30 on oil I can avoid the $1000 trans swap I was told I needed. I love my car, but since I had to buy her a new engine I'v been paying off my father who lent me the money, and I have nothing left to spend.......this is a bit of a last resort for me......

[EvoEatr]

I think I have heard of one story about where someone changed the trans fluid and this problem went away, however what I can say from my experience is once you start getting torque bind its usually to late. My recommendation to you if the fluid change doesnt do it, is to measure the tire circumferences. they should all be within 1/2 in. of each other, also make sure your tire pressures, and wear is the same, this is usually what causes premature wear of the viscous coupler/ transfer clutches... anyways after everything is square with the tires, my bet is that its time to budget for a VC or transfer clutches depending on whether you have and automatic or manual....I believe when I priced a VC for my Legacy it was around $600 for the part...its not to hard to replace and can be accomplished with the transmission in the vehicle? Are you 100% sure that its the front tires skipping and not the rear? almost 100% of my experience with this problem when it comes to failed center diff. is that the rear tires kind of drag across the pavement.

[REXme]

Thanks for the help. I found that the fluid in my trans was a bit low so I topped it up. Turns out a bit low means half a quart. Once the trans fluid was topped up did my usual 30 mile highway drive home. Once I got off the highway near my house i noticed that there was a lot less trans noise, the 1st gear synchro was shifting into first at about 15 Mph and when doing the uturn to park there was very little hopping. Overall the transmission feels a little more accurate and smoother, so tonight I will be draining all my trans and diff fluid and putting clean synthetics in there.

I'm hoping that by doing this I can get a few more years off my transmission, there is a whole laundry list of things I need to fix, and ill be glad if i an skip the trans.

[MainFrame]

although keep in mind that it only happens after driving long distances. If I start the car up in the morning and take it around the block, by the time I get back I am still able to park without any issues, however if I drive my 30miles to work I cant bare trying to pull into a spot.

Further evidence that the center diff is going out. It heats up after driving causing it to lock. Exactly what my car did when the center diff went, if I just hopped in and drove it it was fine, but if I had gone ~100miles and pulled into a gas station the diff would be locked.


If you fix the center diff before it gets too bad then you shouldn't have to worry about the transmission, but if you wait I can see it easily causing something else to break.

[REXme]

A few days ago I replaced the trans and diff fluid. The transmission is very smooth and quiet, but the center diff still locks up, granted its nowhere near as bad as it was before, but the lockup is still present. Not only that but there were a few chunks of metal on the drain plug :-( . My uneducated guess would be that the center diff is coming apart....

Further evidence that the center diff is going out. It heats up after driving causing it to lock. Exactly what my car did when the center diff went, if I just hopped in and drove it it was fine, but if I had gone ~100miles and pulled into a gas station the diff would be locked.


If you fix the center diff before it gets too bad then you shouldn't have to worry about the transmission, but if you wait I can see it easily causing something else to break.