differential additives

[2mtrucks]

I am going to change the gear oil (differentials) in my m1028. Are any additives or friction modifiers needed or recommended? Has anyone ever used synthetics and are there any benefits? Thanks

 

[mikes47jeep]

all I've ever used on all my MV's and cars is regular old 80-90w and never had an issue

if you dont have one a magnetic plug is always a good idea, picks up all the little fileings before they can do any harm

regards

Mike

 

[EZFEED]

Lucas additive is great. I have always used it.

Ditto on the magnetic plug. You can make yours magnetic if its not but here's the trick. dont use regular magnets. Swing by RadioShack and pick up a few rare earth magnets, these little boogers will pick up ALLOT to say the least. Drill into the backside of your plug insert one and cover it with JB Weld or some other strong epoxy. I do this for all of my drain plugs on my vehicles and even replace the original magnets with these magnets. You'd be suprised how much metal fillings they will pick up.

 

[Willie G]

Unless you are using some sort of clutch-type differential lock, you don't need any additives. You can use a synthetic oil if you like, but otherwise any good lubricant of the proper viscosity will do just fine.

 

[AFC1]

Yes, the 14 Bolt rear on your M1028 uses a locker- it doesn't need any additives. The posi-unit in your front Dana 60 will need a bottle of the limited slip additive as it is a clutch-type unit. I have a bottle of the GM additive if you are willing to pay for shipping. Just let me know.... -Larry

 

[2mtrucks]

Thanks for all the info. Will definitly get magnets. Wasnt sure about the front diff but I have some KW posi additive I think will work. No more than its driven synthetic is probably a waste of money although I would consider it if it was a DD.

 

[hobie237]

Interestingly, GM (and thus the TMs) call for an additive to be added. However, Eaton, who makes the Detroit Locker units, says no additive is necessary. Personally I'll trust the company that made the component over the generic GM warning that gets slapped into plenty of manuals whether it's needed or not- but then again, for those who choose to run the (well, any) additive, it won't *hurt* anything, except maybe your wallet. The front posi unit, however, I believe actually *does* need an additive.

I run synthetic trans and gear oils in all my vehicles. The main advantage is that it lubricates better when cold- so when I fire the truck up in the snow everything will be lubed rather than having a gear oil jelly sitting in there. The Miata is the only vehicle that gets synthetic motor oil, though (only Royal Purple, Redline or Amsoil)- none of the other vehicles deserve that.

 

[AFC1]

Lockers do not need any special additive, posi-units do or otherwise you are going to 'chatter' going around corners. The limited slip additive lets the clutches slip a little bit going around turns.

 

[LanceRobson]

The posi-traction front differential calls for a limited slip additive. he additive breaks down with time and use. Follow the TM and LO interval recommendations.

Many gear oils now come standard with the limited slip additive. The bottle or case will state if it does. For example, the Parts Plus 80W90 is a limited slip oil right out of the case at around $34 a case.

Don't confuse the advice about the locker rear axle with your front axle. It could be an expensive "Oops!"

Lance