Oh eternal wise ones of the almighty GRM forum boards, I have come before thee with an almighty stumper of a problem
I recently purchased a '96 Civic CX hatch (base model, no options). I have come to notice that the car is trying to KILL ME ON THE HIGHWAY IN SLIPPERY CONDITIONS! You know that joke with the drift people, "its impossible to drive straight!" well its true with this car. Let me explain:
Whenever the roads get icy/slippy, the rear of the car starts to yaw back and forth. Initially, I thought it was simply because the ruts worn into the highway were wider than the civics track, but this is BAD. I've never had a fwd car do this before. You can be on a dry piece of pavement, then hit a patch of icy road, and the rear end will step out 15+* in either direction at random.
So, that is a description of the problem. Like I said, its like the rear end rotates to the side by itself (yaw in my own definition). It tracks arrow straight/handles like a dream on dry pavement, gravel, and deeper snow.
The only issue the car may have (and I can't even tell yet) is that there seems to be a lot of play in the steering wheel (6* total from when the steering is tight, through the play and tightens again). I have to check this tomorrow if it is actually play, or my imagination. Also, it does have rear drums so one could be dragging (but that would cause it to only slide one way, no)?
Either way, I am at a loss and need some insight. Confused I r
What sway bars are on the car if any? If the sway bars have been upgraded then this might cause the instability, too large of a diameter and the rear end tends to turn really easily.
How fast are you going in the slippery conditions on the highway? I had a 95 civic, that the back end would feel like it was slipping back and forth in wet conditions, I think this was more from how light the car was though.
Andrew
Off the top of my head, I'd first look for excessive rear toe out. On a RWD car, if the front has too much toe out the car is unstable in a straight line at higher speeds. That sounds very much like your problem, just on the other end of the car. This will probably also cause some weird tread feathering. It could also be a difference in wheelbase from side to side (old accident damage?). A quick Google shows rear toe should be around 2mm toe in, front should be 1 to 2mm toe in. Up to 1/4" inch wheelbase difference is acceptable. Both should be pretty easy to check. The toe should be pretty easy to adjust, the wheelbase not so much. But I lean more toward a toe out problem.
On the steering, you should be able to easily check the inner and outer tie rods for wear. Check the wheel bearings, too. If all those are OK, start at the top of the column and go down, checking every clamp etc as you go. Back to old accident damage: it's a collapsible column and if the sliding segments are not tight this will generate a lot of slop. If all those are tight, check the R&P bearing preload adjustment (that's a big nut above/below the pinion housing). Probably not exactly like yours, but it gets the idea across:
My old Civic did that a little every now and then and I was pretty sure it was because of the lack of swaybars but this seems much worse.
gamby
SuperDork
1/29/11 10:16 a.m.
That is odd. Then again--I don't drive on untreated ice all that often and my cars are always on snow tires in the winter. The Civic hatches I've had (as well as the coupes I've had and the sedan I have) never did that, either.
My 99 Si coupe with a 22mm rear sway would get a little twitchy in the snow, but still nothing like you're describing.
If by "icy" you mean "icy" and not "snowy", then it might just be a case that driving on untreated ice is bad no matter how you slice it.
Since it tracks straight on pavement, that's a real puzzler. If a drum were seized, I'd think you'd know about it-is there excessive brake dust on one of the rear wheels?
Second the rear toe inspection. When I put the suspension back in my Sentra, I just kinda eyballed it up and went for a drive.
That was the wrong thing to do. Scary loose darty as either rear tire gained a bit more traction than the other.
My Civic did just this a few times back when it was my daily and use in snow and ice. It was quite simply that I had well worn summer performance tires on the back a newer summer tires on the front, don't recall if they were actually the same brand, but every patch of ice or packed down snow I hit the rear end would come out and get very twitchy.
gamby
SuperDork
1/29/11 10:52 a.m.
LopRacer wrote:
My Civic did just this a few times back when it was my daily and use in snow and ice. It was quite simply that I had well worn summer performance tires on the back a newer summer tires on the front, don't recall if they were actually the same brand, but every patch of ice or packed down snow I hit the rear end would come out and get very twitchy.
Now that I think about it--I remember my 99Si just snap oversteering at a reasonable speed once on a rainy offramp. The culprit was massive camber wear (car is lowered) on the rear tires.
If the rear toe on OP's car is that out of whack, then the tires should be rather chewed up, which will aid in this tailhappy behavior.
pres589
HalfDork
1/29/11 11:01 a.m.
Yeah, get that to an alignment shop, have all corners checked. I would guess there's bad camber and toe here. How are the rear tires wearing? Does it look like every other tread bar or chevron is wearing on the inner edge, like one will be darker, then lighter, then darker again as you look around the wheel? Feathered edges?
Something else you could try is a cross-rotate of the tires, assuming there's nothing directional stopping you from doing so.
Well, this was weird as hell, but everything worked out in the end!
Surprise, it was the right rear wheel being massively toed out. You couldn't tell by looking at it (odd, I know!), but apparently it was at 1* of toe out when factory spec is a max of .16 (or .19). That would do it wouldn't you think? There were no signs of uneven/strange tire wear or anything, it all "looked" perfect.
Well worth the $110 spent at Kal-Tire. And I should have done it sooner, as now the car doesn't want to kill me anymore. It also saved my $220 on tires (I can get 13" Hankook winter tires for $220 installed, I nearly crapped my pants they were so cheap).