Red Line in gearbox and differential?

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Red Line in gearbox and differential?

Post by cory58 » Mon Feb 03, 2020 10:15 am

It's time to service the gearbox and diff on my E12. I've always had good luck with Red Line products in my E30s. Any reason not to use their MTL and correct viscosity gear oil in the E12?

Thanks, Cory
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2015 328i (wife's car)
2001 325i (R.I.P., still missed)

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Re: Red Line in gearbox and differential?

Post by Dale » Mon Feb 03, 2020 3:38 pm

Been using in mine with no issues.


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Re: Red Line in gearbox and differential?

Post by PatinaBeforePolish » Mon Feb 03, 2020 6:42 pm

Have used it in all my cars for years. Like butter. Except the 78 F150, that thing'll run with no oil.
78 F150
79 528i
81 528i parts car
01 540i
86 944
08 X3 don’t judge me it’s there to preserve the others

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Re: Red Line in gearbox and differential?

Post by 528i-1981 » Tue Feb 04, 2020 5:54 am

Same here, definitely noticed the difference with MTL in the gearbox and Redline gear oil in the diff. Shifts are smooth and accurate, and that's with some play in my neglected shifter. Some older posts of FF mention some leaks when changing over to MTL if you're using a thicker oil currently. Maybe some cardboard under the tranny after the fluid change for a couple of days. Mine did not leak.
(oo=00=oo) Eric
1981 528i Manual

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Peter Florance
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Re: Red Line in gearbox and differential?

Post by Peter Florance » Tue Feb 04, 2020 12:20 pm

You may go through reverse light switches more often. It seem to work past the seal and get into the contacts.
Peter Florance
First Fives.Org - The E12 Registry
1981 E-Street Prepared Euro BMW 528i w/3.5L & Megasquirt Fuel Injection

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Re: Red Line in gearbox and differential?

Post by Lock » Fri Feb 07, 2020 2:51 am

I've always used Redline MTL in my gearboxes when it's appropriate.

One additive that has always worked for worn syncros in my gearboxes is "Nulon smooth shift". I buy it in batches.

I've put Redline MTL in and seen how the shifts go. If they're still a little crunchy, add a tube of that. The worst that can happen is nothing.

I'm sure there's others but that one always works for me.
1979 528i 5-speed conversion G260/6, Motronic 1.3 179
1980 Honda CX-500

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