Clunk when 4wd disengages

[jross]

I searched and found a few threads with similar topics but I just wanted to see if this is a fairly common thing with a 93 loyale... i'm considering buying it but want to see if I will need to replace the diff soon or something. It seems like it is just binding up since I couldn't get it to clunk when I was in gravel, so I left it in 4wd and drove on the pavement for like 10 feet and disengaged it, which it then clunked very loudly. And I looked, but obviously don't know for sure if the tires are the exact same diameter or not but they appeared to be the same. Can anyone tell me if this is a common thing with these cars and with it clunking is it a sign of the differential going bad? Or is it just the way these cars behave when you have the 4wd on pavement...

Thanks for any help,

Jason

[Numbchux]

that's the way the behave on pavement, cause you're not supposed to drive it in 4WD on pavement! it is true 4WD, not AWD, so when engaged, the front and rear diffs have to spin at the same speed, when going around a corner, the rear end takes a shorter cut than the front, and therefore spins a touch slower.

 

don't worry about it, unless you plan on driving it in 4 on pavement alot.

[Seahag1978]

Yup, it'll bind on dry pavement, I saw one lock completely. Just put it into reverse and back up a few feet to unbind it before disengaging it. Good luck with it!

[Syonyk]

4WD on anything with less than 10-15% slip is really bad for the drivetrain.

 

Pavement, concrete, packed dry dirt, are all not things to engage 4WD on unless you *really* need it.

 

Loose dirt, gravel, snow, ice, etc - those are all fine for 4WD, and the car will behave a lot better with 4WD engaged.

 

Another trick I use for getting out of 4WD on gravel or dirt or such when it doesn't want to disengage (and I don't feel like stopping to back up) is to hit the brakes hard enough to start sliding a bit. At least with the rear drums, as the front tires start to slip a bit, things free up and it'll drop right back into FWD.

 

-=Russ=-

[zyewdall]

 

Another trick I use for getting out of 4WD on gravel or dirt or such when it doesn't want to disengage (and I don't feel like stopping to back up) is to hit the brakes hard enough to start sliding a bit. At least with the rear drums, as the front tires start to slip a bit, things free up and it'll drop right back into FWD.

 

-=Russ=-

 

Nice trick I'll have to try that next time. The only time I've got it in 4WD on non-slippery conditions is a certain steep bumpy dirt road to a friend's house that it handles alot better in low range, and I go up there at least once or twice a week. When I hit the gravel road at the bottom and try to switch back to FWD, it always binds unless I swerve back and forth while gently pushing the lever down (luckily it's a deserted road so no one sees me doing this...)

[NoahDL88]

I had the clunk problem, turned out it was 175's on the front and 185's on the rear, you might check that out too.

[jross]

thanks guys...I understand the physics of the 4wd I just wanted to make sure that this wasn't a sign of a bad diff. Thanks for the confirmation...I think I'll probably buy the car even though the horsepower is about 40% of my current car...I'm really gonna have to get used to that. Oh well, that's just the nature of older subaru's I guess. Is there any other common problems that I should know about other than normal wear and tear items?

[1985GLWAGON]

Hey guys I know you're not supposed to drive on pavement, I'm not doubting that, and I never use 4x4 on anything but gravel or grass, but I thoroughly read my owner's manual and it actually doesn't say anything about where you can and can't put it in 4x4. I just think that's weird, most pickup's manuals that I've read give the "don't use it on dry pavement" speech, but the subaru manual just says you can engage/disengage 4x4 Hi at any speed but use the clutch to enter or leave low-range, nothing about road conditions.

I just thought that it's odd there's no warning at all, you'd think that back when they sold these at the dealers some idiot owner would have put it in 4x4 right off the lot and never taken it out till the diff. blew up.

[subyrally]

ive found that as long as you arent taking very tight turns in 4wd, nothing happens bet better traction, i dont drive in fwd on back roads, i need the traction when i goof around at speed. ive never had any issues with binding or thunking coming outta 4wd. the only time ive had an issue was when i had a tire get ripped open from a pot hole and i had to change both fronts with a different set of tires.. the issue happened when i fogot to take it outta 4wd while it was sitting there, i tried once i was back in the street. took way too much effort to get it outta 4wd and make a loud clunk. as long as its had the same tires front and back, its never given me any issues.

[Hank Roberts]

You might look hard at the rear tires for wear and scuffing. If it's had a tranny swap it might have the wrong transmission for the car. Mine did for a while (Once the mechanic looked up the serial number from the tag on the transmission, they said it had the wrong ratios for the rear end, rear wheels weren't turning the same as the front even going straight ahead).

 

Symptom: rear wheels while in 4wd were slipping badly on the loosest surface possible -- rain and mud on steep forest roads-- and CLUNK-shudder on switching out of 4wd. Tore the back tires up pretty bad in a week up and down the mountain on those roads, before we figured out not to put it into 4wd at all. Put the right tranny in, symptom gone.