98 Z28

I have a strange 60 rear end and I get what seems to be bad wheel hop or something. I don't know if its the tires or the suspension or both. When going around turns and in reverse sometimes it feels like wheel hop or something it makes a lot of noise or vibration(its hard to describe) in the car and is not smooth but if its really hot out it does not do it or do it as much. Or Sometimes from a stop If i get on it I can feel it seem to like hop. Would some after market LCA's help? Before the new rear end the car would do the same thing in reverse so the tires may be causing the problem in reverse but the other stuff all started with the new rear end.

Manic Mechanic

iTrader: (3)

Do you think that getting on it going around curves in reverse is necessary?

Vernon

98 Z28

Sorry i should have explained it a little better it does it while going in reverse just out of the drive. But when going around turns while just normally driving it does it also. Once in a while if I get on it from a stop it will hop too. I was thinking about getting some lca's and pan hard bar but not sure what will work on the S60 rear ends.

Killer_Bluebird

iTrader: (23)

What kind of differential do you have? Spool? Locker? Limited Slip? That could be the cause.

Manic Mechanic

iTrader: (3)

OK, that's understandable. I was thinking you were kinda out there, lol. So no hard feelings I ended up writing a Diff. 101 so you can get it figuired out.

Killer Bluebird is on the right track. It sounds like you have a mechanical locking differential in that S60. These have racheting teeth on each axle that will pop and or click on pawls similar to a 9" socket-wrench when your wheels are traveling at different speeds like in a turn or when changing directions (fwd to rev). They are designed so that if you "get on it" and one axle side starts slipping the other side will catch it on the next tooth and lock them together until power is relased. These are some of the strongest type for a street/strip car that needs maximum traction along with differential in turns but because of it's mechical racheting you have to accept the noise and jarring that comes with it. There is no fix as that's how they opperate properly. You would have to have a different type of more streetable differential installed to make the car more comfortable. A clutch, torsen, or even a selectable locker (electric or air) would be nicer for a street car.

If you have a spool that mean there is no differential action at all. Both axles are locked together in a common solid hub that holds the ring gear at all times. So when the car is turning the tires are traveling in different circles on the ground, the inside smaller than the outside. Since the tires can't travel at different speeds one will slip or scrub against the road. These are the strongest axles but are not very streetable. They will wear out tires quickly from aways scrubbing off rubber in turns. They are prone to oversteer or power slides especially when the road is wet or loose even with little or no power applied. This is due to the two tires fighting each other for a constant speed through a corner. These are best suited to max effort strip cars or off road trucks that get trailered to events. I doubt a reputible vendor sold you one for a street car but if you bought it used all bets are off. Someone knowing it would be harder to sell could have mislead you to get it off his hands. With this type you shouldn't hear much popping or jarring, just constant tire squeal or "wheel hop" in tight slow speed corners when the condition is most obvious.

If you have a limited slip and it's acting like this it's one of two things it's broken or you don't have the correct type of gear lube and or additive in it.
A mechanical limited slip like the factory Torsen uses worm gears that can only transmit power in one direction in a complex arrangement that prevents power from going to the wheel with the least traction. So they constantly apply power to the axle with the most traction (or highest resistance). These are the most user freindly street diffs because they are virtually unobjectionable in mannerisims while providing excellent grip. The downside is reduced strength compaired to the other lockers. If you have one of these and it's actiong like this then there's a broken component inside and it will need to be addressed and should be before you do more damage or get stuck somewhere. Worst case is you're tooling along at a high speed in traffic and your rear locks up causing you to skid out of control and every one else has to avoid you. Your lucky if there's no collision of any kind.
A clutch type limited slip will act like this if the clutch plate rings, like those in an auto trans, are not in the right kind of lubricant and therefore can't slip over each other in curves when the axles are turning at different speeds. Without limited slip oil/additive they tend to grab each other too tightly so when you turn they will bind up then pop loose a little at a time. This could be your problem, the fix would be to get the proper type and amount of additive and put it in with your gear oil. Usually within 100 miles the clutches are all coated and it works smoothly again. These diffs when working properly are one of the most streetable diffs. They will be quite and virtually unnoticed but still reduce excessive wheel spin on one side at a time. The price for the nice manners is reduced overall grip and that the clutches wear out requiring servicing. This wear rate depends on how hard they are used, but running them without the correct lube only accellerates the wear. These are the most common factory performance differential. Usually by 60K they are notably weak. Bigger tires on a truck or drag strip action in a car will use them up quickly.

Vernon

98 Z28

It's a power lock diff that uses clutches is what i was told when i ordered it from speed inc. Can the tires have anything to do with it too? Sometimes it doesn't even do it if it is really warm and the tires are warm or it is at a minimum. One thing i notice if i go around a turn pretty easy and nail it while coming out of it it will do it. It doesn't really bother me I just don't want to break anything.

Manic Mechanic

iTrader: (3)

Call Speed Inc. and find out if it needs an limited slip additive and if so put some in the gear oil. I can't say myself exactly what that diff is supposed to be like but it sounds a little on the rougher than normal side for a clutch type diff.

Vernon

98 Z28

strange said to use the dodge additive. i may just flush the fluid altogether. when i first got it back it had a small leak so it might not have the right mix of fluid and additive when i filled it back up. its probably about due for a swap it has a little over 1k miles on it.

USMC Devil Dog

I just ordered my S60 and had a Detroit Truetrac w/ 4.10s installed with the order. This was an upgrade from the powertrax diff which is a ratchet locker. Sounds like thats what you have. Looking forward to getting the S60, being a Jeep guy I could go with no other than a Strange (Dana) rear!

98 Z28

I was driving it the other day after changing the oil sending unit and it was like 90* outside it doesn't seem to do it all the hotter it is outside. Could it possibly just be that my gs d3s on the rear are finally done. I've needed new tires they are getting pretty bald.

transam69230

iTrader: (49)

Your not suppose to put any additive in the S60 rearends. At least i know if you have a tru-trac you not. Do you have an adjustable panhard bar, and other adjustable parts? I thinking the rearend isn't centered under the body.

98 Z28

Nope I have no suspension mods that is what i was thinking i might need is a panhard bar. I was thinking about getting a panhard bar and lower control arms. I drove it again today in the heat and it doesn't do it all in 85*-90* weather.