Differential Oil brand choices?
 

My 2000 E320 takes 85w - 90 or straight 90w (owners manual said I could use straight 90w), anyways does brand REALLY matter? I see the price points of different brands in 2Tiers.

1 Insane - MB Gear oil
2Cheap - Liqui Moly gear oil




Mercedes is a $33 per liter
Liqui Moly are $9 a liter or $33 per gallon. Liqui Moly also meets spec too.


Any other brands worth considering?

I would go for the Liqui Moly - we're going to be carrying their whole line soon and did a Q&A with one of their Engineers. Their products are very well made and exceed standard regulations by quite a bit.

Thanks, I'm definitely going with Liqui Moly. It's cheap and in spec. Good to hear their products go above and beyond.

parts store API GL5 80w90 works great too.

remember to remove the filler plug first.

Most of the time i have been using Mobil 80w/90, 85W/90 not easy to find. This time i bought the Liqui moly 85W/90, its quality brand from Germany and had a great fillertube on top. Then again i only drive some thousand km before its time to change again, change it every 2 year. In my head as long as the spec are there you can fill what ever you want, more importan to change at the recomended intervall from car or oil manufactor.

Any gear oil with the API donut stating SAE 80W-90 GL-5 on the package label is fine. Brand makes no difference.

Do not use GL-4. It lacks the EP additive that is necessary for highly loaded hypoid gears.

Duke

Duke,
Understand where you are going with this re: GL-5. What was current when the W123 cars were new?

GL-5 was the standard going back to the seventies and replaced Mil-L-2105 that dated back to WWII. The milspec was cancelled some time ago and the military now uses GL-5.

Decades ago when I wanted to change the axle oil on my 190E 2.6 (one change recommended by MB for new cars at about 1500 miles or so.) I looked at the MB recommendation, and it was 85W-90. I searched in vain, but could only find 80W-90 GL-5, but did see a Pennzoil 85W-90 GL-5. So I contacted them and they said they did not sell their 85W-90 GL-5 gear oil in North America.

I was rather irritated that MB recommended a product for US market cars that was not sold in the USA.

So the Pennzoil 80W-90 GL-5 has been in the axle now for close to 30 years.

Duke

This is what I have been using forever in most of my vehicles. I buy from The Zone and their stuff is packed by Warren last I looked.

same problem with toyota, the factory fill axle oil is unobtanium in USA at parts stores. Its actually an SAE90 EP GL5 gear oil. I believe mercedes benz also filled similar heavy lube in the rear ends of W123 and earlier cars.