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MFactory LSD installation question

Messages
11
Likes
17
Location
Tarpon Springs, FL
#1
I encountered the dreaded clutch pedal issue that a flush didn't fix, so since the transmission had to be dropped anyway, I decided to have a new clutch put in as well as a limited-slip differential. I ordered a MFactory diff with a Ford Performance LSD install kit from Whoosh, as well as new OEM clutch disk/plate, master, and slave cylinders.

I am not a mechanic, and this kind of thing is beyond my capability, so I hired a local transmission shop to do the work. The shop claims to have done plenty of this stuff.

Unfortunately, after dropping the transmission and attempting to swap in the new LSD, the trans shop called me to tell me there was a problem with the replacement bearings supplied by the Ford Performance LSD kit. Specifically, the outer diameter of the rollers appears to be too large to fit back into the casing. I don't know all of the terminology here, so I apologize if I am spewing nonsense. But they claim to have measured the outer diameter of the rollers on the replacement bearing after it had been pressed onto the LSD and compared it to the OEM bearing on the open diff, and it was measurably larger. I went down to the shop in person, and they showed me how the OEM diff drops back in without any force, but the new one is too large. When I asked if it was just tight because it was new, the master tech at the shop swore to me that it wasn't right, and that the bearings were either faulty or the wrong ones.

I called Whoosh to see if it was possible to have the wrong bearings, but Ron swore to me that these are the correct bearings that should work on the MFactory kit. We checked the part numbers, and they were the correct ones he sells for the Fiesta ST. I mentioned to him that they didn't look at all like the OEM bearings on the open diff, particularly because the "cage" that holds the rollers is plastic in the (new) replacement bearing, but the OEM bearing cage is all metal. Ron stated that's just how Ford started making the replacement bearings, and that's the only part they carry.

I was stuck between a rock and a hard place. I went to the Ford dealer to speak to their parts department. They were willing to order new OEM differential bearings (which I assume are the correct part), but they were out of state and the earliest they would arrive is later this week (4 days, likely Friday). They assured me that no other dealer nearby had them, and there was no way to get them faster. I called around to other parts stores, but no one appears to stock these bearings. So I went ahead and ordered them from the Ford dealer for about $100.

The transmission shop of course is not happy since the car will take up one of their bays until the part arrives and is likely to charge me even more money for the hassle. Worse, I'm very concerned that there is no guarantee that the new bearings will be any better when they finally arrive. I'm worried that when the bearings arrive they're going to look identical to the ones that were in the Ford Performance LSD install kit, i.e. plastic cage with the same slightly larger outer diameter.

Has anyone encountered anything like this before?
 


Messages
229
Likes
308
Location
Kalamazoo, MI, USA
#2
I just did an install with the Ford Performance LSD install kit a month ago no problem, although I ordered the M Factory diff and install kit almost two years ago from Woosh. That sounds like the same bearing description that I had. I believe it was a SKF bearing with a green plastic cage for the rollers. Its possible maybe there was a batch of faulty bearings, but that seems like bad luck. Also, it is pretty hard to mess up the simple (IMO for a tech that works on cars for a living ) install.

Unfortunately things like this happen. Hopefully if it is a faulty batch of bearings it isn't the same batch being shipped. Hopefully they will measure and not try to blindly install them if they aren't correct. I would definitely expect at least another billed hour for pressing/removing the old cages and reinstalling them assuming it is correct/different bearings. It is an unfortunate situation for all involved.
 


OP
Troph
Messages
11
Likes
17
Location
Tarpon Springs, FL
Thread Starter #3
Update: things are not good. :(

So about 1 day after I ordered the new OEM bearings from Ford, the transmission shop called me and said, "We actually had matching bearings in stock, so we can use those." I was skeptical given how hard these are to find. I asked for a parts number, and they said, "Well, we have a lot of spare parts that haven't been used, and we matched these. Don't worry, they're the right ones. Trust us, we've been doing this for a long time."

The Ford bearings came in on Thursday, and when I went over to pick them up, I could tell immediately that they were far superior to the SKF bearings from the Ford Performance kit. First of all, they were made in the UK (rather than Brazil) and were all-metal, and seemed heavier. Unfortunately, the shop had already put the transmission together with whatever bearings they found lying around in their shop. I decided to drop them off at the shop anyway, since they had used their own supply, as a sort of "exchange" of parts. Apparently they either broke or lost a connector for the hydraulic line that goes into the slave cylinder, and it was leaking when they got it re-assembled. They had to get a new entire assembly from Ford, which took an extra day.

So yesterday (Friday) they call and say the car is finally done. In-between meetings, I managed to get over to pick it up, but I didn't have much time to drive it. I explicitly asked whether it had been driven, and they said, "Oh yes, it's been test driven, and everything is great!"

Well, when I drove home (only about 5 minutes), I immediately noticed two things. First, from a standing start, releasing the clutch "shudders" a bit. That's definitely not like the original clutch release that was there before, which was nice and smooth. I knew that replacing the clutch would mean there would be a *slightly* different feel (the original clutch only had 22k miles), but I wasn't expecting shuddering. I'm wondering whether this will get any better?

But anyway, the second issue is worse. When accelerating (particularly in 2nd and 3rd gears) I noticed an odd hesitation at lower RPMs, as though I had to give the car significantly more throttle to accelerate than ever before. And then, as soon as I hit maybe 3k RPMs or so, there is a surge in power as something "releases". It honestly feels like there is some extra friction, and then the friction kind of dissipates all of a sudden.

Sadly, I didn't have time to play with it more and take it right back to the shop, which is my mistake. I had to get back to work.

So today, I took it out and re-confirmed both observations from yesterday (shuddering clutch release, plus odd hesitation when accelerating), plus a new one. In a parking lot, I tried a tight turning circle... and after about 5 seconds, there is a really bad whining/squealing noise coming from under the car, especially as I pick up a little speed.

Yuck. At this point I'm not sure what's going on, but it's not right at all. I'm no mechanic, but I'm suspicious of the "found them lying around" bearings they put into the differential. If one or more of those bearings were bad, couldn't that explain both the "friction hesitation" and "squealing when turning" symptoms?

And is there anything that can be done about the shuddering clutch release?

I'm pretty depressed about the car at this point. I've spent tons of money on it, and managed to make it worse.
 


gtx3076

1000 Post Club
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1,181
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1,375
Location
US
#4
Update: things are not good. :(

So about 1 day after I ordered the new OEM bearings from Ford, the transmission shop called me and said, "We actually had matching bearings in stock, so we can use those." I was skeptical given how hard these are to find. I asked for a parts number, and they said, "Well, we have a lot of spare parts that haven't been used, and we matched these. Don't worry, they're the right ones. Trust us, we've been doing this for a long time."

The Ford bearings came in on Thursday, and when I went over to pick them up, I could tell immediately that they were far superior to the SKF bearings from the Ford Performance kit. First of all, they were made in the UK (rather than Brazil) and were all-metal, and seemed heavier. Unfortunately, the shop had already put the transmission together with whatever bearings they found lying around in their shop. I decided to drop them off at the shop anyway, since they had used their own supply, as a sort of "exchange" of parts. Apparently they either broke or lost a connector for the hydraulic line that goes into the slave cylinder, and it was leaking when they got it re-assembled. They had to get a new entire assembly from Ford, which took an extra day.

So yesterday (Friday) they call and say the car is finally done. In-between meetings, I managed to get over to pick it up, but I didn't have much time to drive it. I explicitly asked whether it had been driven, and they said, "Oh yes, it's been test driven, and everything is great!"

Well, when I drove home (only about 5 minutes), I immediately noticed two things. First, from a standing start, releasing the clutch "shudders" a bit. That's definitely not like the original clutch release that was there before, which was nice and smooth. I knew that replacing the clutch would mean there would be a *slightly* different feel (the original clutch only had 22k miles), but I wasn't expecting shuddering. I'm wondering whether this will get any better?

But anyway, the second issue is worse. When accelerating (particularly in 2nd and 3rd gears) I noticed an odd hesitation at lower RPMs, as though I had to give the car significantly more throttle to accelerate than ever before. And then, as soon as I hit maybe 3k RPMs or so, there is a surge in power as something "releases". It honestly feels like there is some extra friction, and then the friction kind of dissipates all of a sudden.

Sadly, I didn't have time to play with it more and take it right back to the shop, which is my mistake. I had to get back to work.

So today, I took it out and re-confirmed both observations from yesterday (shuddering clutch release, plus odd hesitation when accelerating), plus a new one. In a parking lot, I tried a tight turning circle... and after about 5 seconds, there is a really bad whining/squealing noise coming from under the car, especially as I pick up a little speed.

Yuck. At this point I'm not sure what's going on, but it's not right at all. I'm no mechanic, but I'm suspicious of the "found them lying around" bearings they put into the differential. If one or more of those bearings were bad, couldn't that explain both the "friction hesitation" and "squealing when turning" symptoms?

And is there anything that can be done about the shuddering clutch release?

I'm pretty depressed about the car at this point. I've spent tons of money on it, and managed to make it worse.
I have to say your experience is not all that different from mine when I tried to put in a built motor into my mazdaspeed 3 many years ago. What I took away from this is that unless you have a rock solid builder with a warranty, or you can do the work yourself, be very careful when deviating from stock on a daily driver. I spent $8k trying to making a fun daily and ended up dumping the whole thing for $2k.
 


OP
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Messages
11
Likes
17
Location
Tarpon Springs, FL
Thread Starter #5
Yeah, finding technically competent people these days is almost impossible it seems. This was a highly rated transmission shop supposedly. At this point I just need guidance about what is probably wrong, because I've lost trust that they know what they're doing. If I have them open it back up to replace the bearings again, I assume that means they're going to have to replace all of the transmission bolts yet again? That diff install kit was horribly expensive when I saw what was in there, especially considering that the bearings they shipped weren't even OEM parts.
 


kevinatfms

Senior Member
Messages
873
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923
Location
Germantown
#6
The polymer cage bearings are typically an upgrade to the all metal cages found in OE applications. The polymer cage reduces friction and drag in the bearing assembly. It also is slightly quieter than the all metal unit at certain harmonics.

Only downside is heat tolerance depending on the composition of the polymer material. Usually with the polymer cage, the friction reduction is enough to eliminate that worry but there is still a lower limit for temperature than the metal cage bearings which can be up and over 500F.

I would ask the shop if they set preload correctly or not. They may have matched bearings up but did they actually setup and preload the diff correctly per the WSM or did they just slap the thing in there with the original shims?
 


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