Replacement for Torsen limited slip?

[Koshunae]

Not long ago I posted about my 8.8 out of a Fx4 Level II with a bent axle shaft. That's been resolved! However there's still a few things that I have minor concerns about. The R7 in this particular rear had a Torson LSD, instead of the clutch style limited that I was expecting. I'm not bummed about it, but I really don't know how to feel about it.

Onto the concerns; It seems louder in the rear than I was expecting. They say that a torsen shouldn't be any louder than a standard differential but I just can't see how it's possible to be just as quiet with all the worm and spur gears inside of it. Is it normal for them to be a little louder than an open diff? It kind of sounds like I have loud tires. Also the torsen doesn't seem to lock the way I would expect a LSD to lock. From a stop on gravel it will spin both tires for about 3 feet and just let one wheel spin after. On wet pavement from a stop in a turn, it seems to act more like an open differential. I'm not very versed in torsens so I'm not sure exactly how the torque bias works. When I think limited slips, I think both tires spinning and whipping me around in circles.

My other concern is a rumble that I have around 60 to 64mph. I didn't replace the wheel bearing from the bent axle shaft, it looked fine and felt fine so I ran with it but I do have a replacement bearing and seal should I need to replace it. I checked the pinion and it doesn't budge up or down, side to side. The rotational free-play seems normal, about what I would expect. I recently replaced my driveshaft u-joints. Any ideas?

And my final concern is a slight vibration at speed when I push the clutch in. It didn't do it before the swap, again, checked pinion and u-joints. There's no other whine or noise associated with it. I don't hear it when coasting with the clutch out or accelerating, just whenever I push my clutch in and disengage. That one really has me going for a loop.

Any ideas?

 

[adsm08]

My Torsen is nice and quiet. They do have an unusual torque bias, which is kind of the point. They are supposed to be able to operate more like an open diff in turns, but still give the limited slip benefits on straight aways and low traction situations.

 

[Bird76Mojo]

The Torsen is an odd duck for sure. Mine is quiet as any other rear axle. The torque biasing is odd, and I've never driven a truck with a Torsen in difficult off-road situations. I put it in my v8 street truck and I should have probably went with the clutch type for street use. Regardless of that, I can still overpower the grip the tires have on demand and spin both. If there's a little gravel, sometimes I'll have a little one wheel peel..

 

[Koshunae]

My Torsen is nice and quiet. They do have an unusual torque bias, which is kind of the point. They are supposed to be able to operate more like an open diff in turns, but still give the limited slip benefits on straight aways and low traction situations.

The Torsen is an odd duck for sure. Mine is quiet as any other rear axle. The torque biasing is odd, and I've never driven a truck with a Torsen in difficult off-road situations. I put it in my v8 street truck and I should have probably went with the clutch type for street use. Regardless of that, I can still overpower the grip the tires have on demand and spin both. If there's a little gravel, sometimes I'll have a little one wheel peel..

Given the history of this axle, I bought it off a guy who had been sideswiped, hence the bent axle at the beginning. Do either of you think it's more likely that the wheel bearing is beat and giving me these symptoms? Also is the center plate directional? When I was taking the differential lock bolt out, the plate just kind of fell out and into the oil catch pan so I didn't get a chance to see the direction. It doesn't look directional, just like a piece of machined block lol. I don't hear any other noises out of it that really concern me. No clunks, bangs, grinds, or rattles. Just the humming and vibration under certain circumstances. The hum is like I have maybe a slightly larger all terrain tire or maybe a little bit of weight in the back of the truck. I have a k2500 on 37" military tires and the sound is absolutely nothing like that, it's just kind of in the background. If I turn the radio up, I don't hear it. Am I just being overly sensitive to it? The ranger is my daily and I really want it to be right lol

 

[Bird76Mojo]

Coming from a wrecked truck, it could be anything. It's anyone's guess. The housing itself could be bent, causing alignment issues between shaft, bearings, gears, etc..

If the housing is bent, it very well could be tire noise as the truck "drags" the tire down the road out of alignment. Though I'd think there would be tread wear showing up rather quickly..

An alignment shop could tell you if the rear wheels are parallel with the truck or not.

 

[gw33gp]

I have a lot of experience with Torsen in all kinds of conditions after 265K miles on my Ranger. The Torsen makes no noise. It has a higher torque bias than a clutch type LSD. When taking out while turning it is easy to screech the inside tire if you accelerate a little to fast due to the Torsen trying to keep both tires spinning at the same speed. The Torsen seems act more like a locker when accelerating. The harder you accelerate the more it acts like a locker.
I like the Torsen so much that I also had one installed in the front.
Your noise is not originating from the Torsen. When going straight the Torsen is not even working unless you lose traction on one side or you have one tire larger than the other. It must be a bearing or a bent axle housing as suggested before. If the axle was bent in an accident, you can bet that is not all that was damaged. If everything ese checks out, you might check the backlash and wear pattern on the ring and pinion.

 

[Koshunae]

I have a lot of experience with Torsen in all kinds of conditions after 265K miles on my Ranger. The Torsen makes no noise. It has a higher torque bias than a clutch type LSD. When taking out while turning it is easy to screech the inside tire if you accelerate a little to fast due to the Torsen trying to keep both tires spinning at the same speed. The Torsen seems act more like a locker when accelerating. The harder you accelerate the more it acts like a locker.
I like the Torsen so much that I also had one installed in the front.
Your noise is not originating from the Torsen. When going straight the Torsen is not even working unless you lose traction on one side or you have one tire larger than the other. It must be a bearing or a bent axle housing as suggested before. If the axle was bent in an accident, you can bet that is not all that was damaged. If everything else checks out, you might check the backlash and wear pattern on the ring and pinion.

Everything fell right into place with the swap, the pins on the springs found the axle painlessly. I figure if the axle itself was bent, I would've fought with it while going in. I don't have a perfect straight edge, but even so I can't see anywhere to really determine if the housing is bent. Giving it a really thorough eyeball inspection, it seems fine.

I just got back inside from checking everything out on it. I'm pretty sure my vibration is coming from the transmission itself. There's a good bit of play on the front yoke on the driveshaft and I can hear a little noise inside and at the front of the transmission when I push up and down on the yoke. I'm pretty confident in that being my vibration at least. I checked both axle shafts, The passenger side axle shaft has a little more vertical play than the (new) driver side. I don't drive the truck very far generally so I suppose on my next weekend, I can pick up some gear paint and check my wear pattern to see if anything internal got tweaked.

 

[fastpakr]

For what it's worth, the last I checked you could get the replacement Torsen unit from the manufacturer for $325. Ridiculously good deal.