75-90 LS mobile 1 synthetic gear oil in front dif?

[leveled]

I am thinking of running this in my front dif. on my Kubota MX5100 4x4.

I read the discussion on the super udt comparison and came to the conclusion to run the heavier weight oil also was advised by dealer. I am a bit confused on if the ls portion of this oil, will this hinder something or does it not matter? I am embarrassed to say I don"t really understand limited slip? I have a good source to purchase this oil at a discounted price and I like to run Mobil 1 fluids.

Thanks

 

[Gary Fowler]

I know that Kubota manual says that you can run SUDT fluid in the front differential but my dealer's service manager recommended a heavier weight oil like 90w gear oil which he thought was better for the gears. Of course a full synthetic would be even better.

 

[leveled]

yes my manual states that I can run 80 - 90 or super udt or udt. I am just confused if the limited slip portion of the mobile 1 75- 90 will be bad for the tractor?

 

[PHILIP8N]

The LS additives will not have any effect with the open front differential on your Kubota. The LS additives are friction modifiers so LS clutches or cones do not chatter when turning. The LS additives actually take away from the locking performance of the LS differential, but make it more driver (and complaint free) friendly. No issues, M1 75w-90 is a great oil for front axles. Philip.

 

[ray66v]

Though SUDT, is on the thinner side for viscosity of hydraulic transmission oils, 75-90w, or 80-90w gear oil, is not substantially heavier than hydraulic transmission oil.

It's a popular misconception. But, gear oil is not rated on the same scale.

People think of gear oil as heavy thick oil. Some gear oil is. 80-90w is not like that.

You can see this by doing a pour test. OR, your own timed viscosity test.

They are both about the same viscosity. Both are lightweight GL-4 or better, gear oil. That's why they are interchangeable in many applications.

For reference, at room temperature, 30w motor oil, 80-90w gear oil, and Hydraulic transmission oil, are all about the same viscosity.

The viscosity of a given oil, does vary widely by brand.

The reason gear oil is generally better in a differential is, EP designated gear oil, is designed specifically for applications with hypoid gears. i.e. a differential. This is because, hypoid gears create extreme pressures.

A synthetic EP gear oil is usually ideal.

Viscosity Charts - Bob is the Oil Guy - Bob is the Oil Guy

 

[Z71]

Fyi...........................................................................................

Chatter is essentially the build-up and release of energy between the differential clutch packs in a limited slip differential during operation. This phenomenon often occurs when torque is transferred between the clutches or when rotational speeds change. During the stick-slip phase, energy is built up to a point where contact between the clutch plates change between static friction (stick) and dynamic friction (slip), resulting in noticeable vibrations. It is this vibration that causes an audible chatter or ratcheting to be heard within the differential. While certainly an annoying characteristic, there is typically no mechanical damage occurring to the differential. It is most often noticed in parking lots or slow driving while turning where the outside wheel turns faster than the inside wheel.

In an effort to control this chatter, friction modifiers are often used. These additives result in a smoother transition between the two states of friction: static and dynamic. Static friction occurs when the clutches physically lock together, while dynamic friction occurs as the clutches are slipping, ergo Limited Slip Differential.

 

[MHarryE]

At the first oil change I went Mobil 75W-90 synthetic in the front axle on my L5740 and a front wheel bearing failure has been my only issue with the tractor now at 800 hours. Two years ago I had a project that involved a lot of load and carry that I am fairy certain cur the bearing life significantly. Did Mobil 1 synthetic stretch out the failure? I can't conceive how it could have reduced life but in fact I did have a failure. I still believe in a Synthetic for that application but my M135 GX with electric clutch locking front diff - I am going to stick with Super UDT2 in that. Too many unknowns for me with that electric clutch in the axle. The L5740 is still running 75W-90 synthetic.

 

[fortec]

If you don't actually need LS oil, i.e. if you have an open differential, it's best not to use them. LS additives typically have a detrimental effect on oxidation and seal performance, so whilst they are necessary in an LS diff they are best avoided otherwise.

 

[ccsial]

If you don't actually need LS oil, i.e. if you have an open differential, it's best not to use them. LS additives typically have a detrimental effect on oxidation and seal performance, so whilst they are necessary in an LS diff they are best avoided otherwise.

Old thread but I wonder if Mobil 1 75-90 Gear lube would cause seal problems on a 2005 L3400? It says it has LS modifier included.

 

[fortec]

I can't tell you that but attached is a link to the GM website that shows approved gear oils. The ones prefixed GOLS wre of course for LS applications but the ones simply prefixed GO do not contain LS friction modifiers.
DEXRON(R) Gear Oil
I hope that is of some help in selecting an appropriate lubricant