Rear End Sliding Out

[99SUS SFD]

So for some time now, when I hit some cracks in the pavement, if I'm turning at all the rear end will kinda spin out from underneath me. It will slide sideways while it's hitting the bumps. Now I'm not sure if it's from these lower profile tires that I've never had before or if it's suspension related. I'm leaning towards suspension because there are some rattles in it. I've tested the struts by jumping on the rear bumper and they seem ok. Anything obvious to check for?

[rougeben83]

So for some time now, when I hit some cracks in the pavement, if I'm turning at all the rear end will kinda spin out from underneath me. It will slide sideways while it's hitting the bumps. Now I'm not sure if it's from these lower profile tires that I've never had before or if it's suspension related. I'm leaning towards suspension because there are some rattles in it. I've tested the struts by jumping on the rear bumper and they seem ok. Anything obvious to check for?

how much psi are you putting in your tires?

[peugoby]

Get your alignment checked out. Sounds like an issue of too much/little camber. Also, check your tire pressure like Ben mentioned.

..... honestly it sounds kind of fun! :lol:

[99SUS SFD]

I'll check the psi, but I have them towards the max for the tire. I can't remember off the top of my head.

Haha, it can be fun sometimes, but not when you're cruising at 65 down some crappy VT roads and it slides out from under you when you're not even turning the wheel!

[Huffer]

I'm leaning towards suspension because there are some rattles in it. I've tested the struts by jumping on the rear bumper and they seem ok. Anything obvious to check for?

Jack the rear end up and see if there's any leaks around the struts. IMHO the "bounce" test is only useful if the struts are COMPLETELY busted. My old BD was rolling around quite comfortably for several months with blown struts and passed the bounce test all the time. I only knew they were busted because when I parted the car out, I took the struts apart and the strut body sank straight down - not quickly, but if there's not enough pressure in the housing to resist gravity...

I forget if your car is 4EAT or 5MT, but if it's 4EAT your traction is front biased unless you have the gear in D3 or lower.

[jey]

Rear tires could be overinflated, should be about 2 psi lower than the front. Rattling could be from a disconnected/broken sway bar, which could produce such issues too.

[99SUS SFD]

I'll have to get her in the air and check the struts for leaks and check the sway bar. I was thinking along the lines of sway bar because of the rattles as well as the way it comes around on the bumps.

I know for a fact that all the tires are aired to the same psi, so I'll drop the rears a bit.

FWIW, all SUS's came as a 4EAT unfortunately...

[gryffinwings]

I'll have to get her in the air and check the struts for leaks and check the sway bar. I was thinking along the lines of sway bar because of the rattles as well as the way it comes around on the bumps.

I know for a fact that all the tires are aired to the same psi, so I'll drop the rears a bit.

FWIW, all SUS's came as a 4EAT unfortunately...

Aren't the SUS's just Legacy Outbacks? I don't think they were all just autos, even the 2000-2004 Outbacks came with Manual. Just a little confused about that point.

[jey]

Yeah but the SUS was only offered in the Limited trim, which was automatic transmission only.

[decke48]

hmm. sound like somethings broken.

[rougeben83]

I'll check the psi, but I have them towards the max for the tire. I can't remember off the top of my head.

Haha, it can be fun sometimes, but not when you're cruising at 65 down some crappy VT roads and it slides out from under you when you're not even turning the wheel!

You realize you should have them set at the psi that's on your door sill right? It's going to be around 30-35psi, NOT 45-50psi depending on the tire. The max on the tire is not what you want to be running unless youre autocrossing or something to prevent debeading.

And before you do anything else please check that. It may be as simple as a 10psi too much in your tires thats causing your problem.

[1-3-2-4]

So for some time now, when I hit some cracks in the pavement, if I'm turning at all the rear end will kinda spin out from underneath me. It will slide sideways while it's hitting the bumps


I had that same issue with my 95 Impreza.. it was FWD and had blown shocks and no RSB.. I remember hitting a depression in the road while the road made a left hand turn up the hill.. only doing like 30 when I tried to miss the depression for the manhole cover and damn when I hit it the whole ass end started to slide out.


Also for the person who said set the PSI to what it said on the door seal I did that once (I know I should of checked the tire) I had a blow out because the max on the door seal was the max for the Kumho tires I had on the impreza.. tire just went flat just as I got in the 3rd lane on the highway.. also the same time I lost reverse in that car too..

[rougeben83]

[quote="99SUS SFD":y07lfo3f]So for some time now, when I hit some cracks in the pavement, if I'm turning at all the rear end will kinda spin out from underneath me. It will slide sideways while it's hitting the bumps


I had that same issue with my 95 Impreza.. it was FWD and had blown shocks and no RSB.. I remember hitting a depression in the road while the road made a left hand turn up the hill.. only doing like 30 when I tried to miss the depression for the manhole cover and damn when I hit it the whole ass end started to slide out.


Also for the person who said set the PSI to what it said on the door seal I did that once (I know I should of checked the tire) I had a blow out because the max on the door seal was the max for the Kumho tires I had on the impreza.. tire just went flat just as I got in the 3rd lane on the highway.. also the same time I lost reverse in that car too..[/quote:y07lfo3f]

I seriously doubt you had a blow out from running 30-35psi like what it says on the doors of most passenger cars. More likely you had a slow leak you didn't know about until the tire lost enough air that it happened.

[ccampbell2546]

The same thing happens to me too. I found out that it is due to a broken driver's side front endlink. So the front swaybar is disconnected and causes the rear to grip more and slide around.

[99SUS SFD]

I haven't gone to the gas station to let some air out of the tires (because I don't have a gauge at home) but I did crawl underneath the rear end and started grabbing stuff. Everything seems tight. I guess I'll check up front too and will air down the tires soon. I still have a feeling I have a blown strut or two back there because of all the rattling.

[99SUS SFD]

Just went and checked underneath the front end. Everything looks good under there too. Well...except for the large amounts of oil that seem to be dripping from somewhere...

[1-3-2-4]

I haven't gone to the gas station to let some air out of the tires (because I don't have a gauge at home) but I did crawl underneath the rear end and started grabbing stuff. Everything seems tight. I guess I'll check up front too and will air down the tires soon. I still have a feeling I have a blown strut or two back there because of all the rattling.

My impreza used to do that rattle it was annoying.

[rougeben83]

I haven't gone to the gas station to let some air out of the tires (because I don't have a gauge at home) but I did crawl underneath the rear end and started grabbing stuff. Everything seems tight. I guess I'll check up front too and will air down the tires soon. I still have a feeling I have a blown strut or two back there because of all the rattling.

blown strut is easy, just look at it and see if there's a lot of oily residue on the body, you can also lift the boot up to see if there's any oil weepage. Last resort you can always do the bounce test...rule of thumb is the strut is supposed to stop the spring/car from bouncing up and down without 3 cycles or something like that...

[99SUS SFD]

Well I aired down to the suggested psi today even though the wheel and tire size is different from OEM. I had 40psi all around and am now down to 29 in the front and 28 in the rear. We'll see what happens.

[Huffer]

You should run 34/34 or 36/36. I find that 29 is too low and allows too much sidewall roll.

[99SUS SFD]

Yeah that's what I was thinking, I'll probably drive around a bit tomorrow and see if the problem has lessened.

[jey]

You should run 34/34 or 36/36. I find that 29 is too low and allows too much sidewall roll.

Front should be higher than the rear to keep the rolling diameters as close as possible, which is important for Subarus.

[99SUS SFD]

Yeah I've got the fronts at 38 and the rears at 36. The problem is lessened but not by much (either at the 28/29 psi or the 36/38).