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Is it normal for the diff to not have the Mfactory logo on the diff itself? The box says Mfactory and it has the correct part number on it. I ordered it through one of the authorized dealers, and it had to be shipped in.
 

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Discussion Starter #22
Yes, it's normal. If it arrived via YCW or MFi, it's fine :)

We only made 1 batch of the MTX-75 diffs, which didn't have the logo on them. The subsequent batches will have the logo though.

Sorry for the confusion :(
 

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Perfect thats great, huge weight off my shoulders lol. Also, it has some brown spots on it, it looks like surface rust to be honest. The unit came oiled. If i rub it vigorously it comes off. Should i be concerned? Should i wipe a coating of oil over it to further protect it also?
 

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Perfect thanks guys, quality product. No casting flaws, no burrs, very very nice piece. Cant wait to get it installed! I will be doing a full write up and review in the spring when it goes in the car!
 

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Just thought I'd chime in here on the subject of oil and lube used in an ATB(gear) type diff. As we all know the torque balance etc depends upon the amount of friction on the planet gears when the diff is operating. FYI some of the Quaife ATB diffs have been offered with 'friction buttons'..these are inserts at the thrust end of the planet gears that alter the amount of friction..If you understand the operation of an ATB unit you can also work out that the type of oil used also has an effect on the operation. For example a high film strength oil will reduce the amount of friction and drag on the planet gears when in operation and also changes the amount of resistance and torque transfer.Worth a thought before you throw in heavy 'gear oil' types to a trans fitted with an ATB diff...also never use ATF type lubes in any trans with an ATB..wear rate goes up...a lot!!
 

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Terry - Do you have any thoughts on the oil to use in a MTX-75 with the plate-type diff? Or maybe asked another way: Do you have any thoughts on using the MFactory suggested Torco MTF or RTF being used in a MTX-75? If MFactory requires using certain oils to maintain warranty coverage then it'll be down to the best of those choices I suppose.

I've got a Brand Q ATB in my car right now (always run with Ford Honey, a little over 200k on the transaxle itself) but am looking quite a ways down the road... Get a set of set of MTX-75 internals for my autocross Focus rebuilt by you and possibly moving the ATB to my recently purchased "street" Focus when I'm in doing the clutch eventually. That would of course mean an upgrade in the autocross car to a plate-type from MFactory...
 

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Discussion Starter #29
We don't "require" our customers to use any specific oil, although we do recommend the Torco fluids for our Honda customers. For other models, we always say to use whatever they have had good experience with :)
 

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Good to know. Terry has been involved with the MTX-75 longer than Ford has been selling the Focus... I'd imagine he might have some input on plate-type diffs with the Ford "honey" fluid (fully synthetic if I recall) that's recommended for the MTX-75. I'll be sure to post how things go if I ever get to the point of doing all this transaxle swapping.
 

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I'd like to do an LSD to my SVT in the near future, especially if I force induce the engine… I was more than willing to pay the price of the Quaife, but I'd like to see if this is a possibility with the SVT's Getrag transmission.
 

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I'd like to do an LSD to my SVT in the near future, especially if I force induce the engine… I was more than willing to pay the price of the Quaife, but I'd like to see if this is a possibility with the SVT's Getrag transmission.
they do one... its listed on their website.. it was more expensive than the one for the MTx-75 iirc
 

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Bias Ratio

Can the M Factory ATB unit have the bias ratio 'tuned' by adjusting the preload on the internal gears as in the Torsen (by shims) or as in the Quaife (by the Bellville washer stack) I refer to the white paper of testing written by John Trout, University of Texas ,May 2011. Does the M factory ATB use shims for this or some spring pack stack??
 

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Discussion Starter #34
The washers don't change the Bias Ratio, but just the pre-load of the gears against the housing.

To change the bias ratio, we change the angle of the helical gears. At the moment, we only have our higher angle bias for Honda and Mazda applications. We could make them for the MTX-75, but would need to see how many people would be interested in this as it's a whole new set of internals we have to make.
 

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I'm sure the pre load on the gears does affect the bias ratio..Example..a Quaife with the std 6 Bellville washers runs at 68% bias on accel and 64% bias on braking..add a 0.004" shim and that changes to 70% on accel and 65% on braking. Agree the overall bias is by gear cut and friction (includes type of lube used) but the shims can fine tune that a bit.What is the current bias on the M Factory ATB?
 

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Discussion Starter #36
A Helical LSD won't work on braking/deceleration, as it requires torque to function (it's a torque sensing differential)

The standard Quaife had a bias ratio of 2.1:1, so is around 66% or thereabouts. Ours has the same ratio

Sent from my GT-N5120 using Tapatalk
 

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Well I guess we will have to agree to differ on this one..

You may want to take a look at the paper I mentioned...


The Analysis and Testing of the Quaife Torque-Biasing Differential
By

John W H Trout

Master of Science in Mech Eng

University of Texas at Arlington
May 2011


It has a lot of info in it....
 
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