190e Differential Fluid
 

Hi folks,

I have searched the forums and came up with three different choices. See below:

Liqui Moly GL-5 75W-90 fluid

Liqui Moly GL-4+ 75W-90 fluid

Redline 75W-90 Gear Oil fluid

Just inquiring what is the best brand fluid recommendation to use? Thank You!

Mobil1 will be cheaper, easier to source, and do the same job.

I can usually find valvoline synpower 75w90 at parts stores quite easily and with a lower price tag too.

I personally like to use mystik 80w90 from orielly parts or tractor supply on older differentials asking for an older spec heavy gear oil.

I never use synthetics for differentials. Some vintage cars use leather diff seals, which are completely transparent to synthetic lubes. I don't tknow whether this is the case with the 190d, but better safe than sorry.

You don't need an expensive "synthetic" 75W-90 GL-5. Any 80W-90 GL-5 is just fine. Brand makes no difference. Just make sure the label includes the API "donut" with SAE 80W-90 GL-5 spelled out. DO NOT USE ANY GL-4. GL-4 lacks the EP additive (what gives GL-5 its pungent odor) required for hypoid gears.

If it's a 16V and you're doing a complete axle fluid change you'll need some limited slip friction modifier - same as what any cars with clutch type LSDs use. The NAPA p/n for a four ounce bottle is NCB4285V.

Duke