Lubrication order M51A2: oil types

[Robo McDuff]

OK, please tell me that I am wrong and misunderstood the US volume scales and conversion from quarts to liters (or give me a good address to a loan shark).


Following the Lubrication Order, my 1973 M51A2 needs
- about 21 liters of oil for the engine itself
- about 28 liters of oil for the drive train (gearbox, transfer case, differentials etc)
- about 10.5 liters of oil for the steering
- about 35 liters of oil for the dump hydraulics

Using standard over the counter prices in the Netherlands this would set me back about 450 EUR not counting the dump hydraulics nor the fuel - and oil filters! Have to find a cheaper source.

Engine oil: most common used here is 15 W 40, but one guy from my garage recommended 20 W 50. The latter has specification exceeding Mil-L-46152 B/C. Any comments? Or do these engines need un-doped oils (not likely for a 1973 truck)?

Drive train: available here is 80W 90, API GL5 standard, exceeding Mil-L-2105 B and CCMC G2/D1 standards. Sounds ok?

Hydraulics. Bit at a loss here what the current useful European alternative is. Standard used here for heavy machinery is hydraulic oil according standard ISO VG 32 and DIN 51524, at about 15 Eur per liter. Not sure if you still can get the straight-grade 10 engine oil, if that is the equivalent of this OE/HDO 10.

Please advice what is the best deal for this truck. It has about 3 000 miles and less than 500 hours on the counter. Probably the last time anybody changed anything was in 1986. Top quality oil would be nice, but killing and probably unnecessary in this engine.

 

[gimpyrobb]

The 21 liters for engine oil sounds about right, 20.8 is what I got. It certainly isn't cheap, is it!?
I use 15w40, I would think 20w50 would be hard on the oil pump if you are anywhere that gets cold.
Gear oil sounds good.
I thought about using 10wt motor oil for hydraulics, but was told not to. The hydro oil has additives that is better for the parts in a hydro system.

 

[Robo McDuff]

As to the engine, most seem to agree with you that simple 15W 40 will do the job nicely. Drive train is clear, if I can get the stuff cheaper I will use the 80W90

....
I thought about using 10wt motor oil for hydraulics, but was told not to. The hydro oil has additives that is better for the parts in a hydro system.

That seems to be the point with the most variations, especially regarding the power steering. I think I can get 10 W oil, and off course all kind of hyrdaulic oils.

Here we often have moderate temperatures. Winters are average -5, althoug occasionally there are a few days of cold spells with below - 10 degrees celcius, seldom below - 15.

Warm summer days normally are aro0und 25 to 30, sledom higher.

Is there a reason to use different oil in the power sterring unit and the dump unit?

 

[gimpyrobb]

Its been a while since I decided what to use. If I remember correctly, I used hydraulic oil for the PS system, since I bought SO much of it for the wrecker bed.

 

[Robo McDuff]

Ok. Some prices for comparison. I changed it to $$ and gallons. UNfortunately, the $$ took a dive again; in June one Eur bough you $$ 1.20, today its $ 1.40.

15W 40 .. $ 11.4 per gallon (11 Euro per 5 liters)
GL5 80W 90.. $ 17.6 per gallon (3.5 Euro per liter)
10W .. $ 20.8 per gallon (4 Euro per liter)

Big problem now is, even seeing the filters for air, oil and fuel, the company could not figure out which type to use: the numbers specified did not give a match to a current type now used Europe.

Does anybody has any non-military filter specification (like from walmarts or any regular truck supply company)? Maybe with that they can find out the correct equivalents.

 

[doghead]

Can you name a few of your popular name brands?(filters)

 

[Robo McDuff]

Oil filters: professionals use fram filters for small cars. This company for trucks used two systems to search for cross references, one of them Mann-Hummel.

I finally found and will buy the original filters (more or less) through a dump shop called Reomie. Pictures will follow later. Man, do they have trucks there . Jeeps, Deuces and 5-tons, whatever you want. Prices ranging around $$ 10,000 for trucks in driving but definitely not mint condition, without registration papers. Wonder if they ever sell one.

Whatever, the 2 oil filters and 3 fuel filters were about $ 22 each, the air filter was about $ 90. Expensive, but I have no choice and, more important, no time left (having it send to the Czech Republic without checking if they are the good ones is not an option and can be a very expensive and frustrating exercise). And I bought a set of window wiper blades for about $ 10. D@#$m, forgot the door lock mechanism. Have to go back anyway, did not have enough money with me.

 

[Robo McDuff]

Decision time. Don't know which oil was in the truck power steering system but is there any good reason why I should NOT use the specified 10W Oil? This I can get for a reasonable price.

 

[doghead]

10W will be fine. Typical hydraulic oil.

 

[Robo McDuff]

10W will be fine. Typical hydraulic oil.

Thanks.

Next point, maybe an overworried newby one. Quite unexpectedly, I have to drop everything and race back to the Czech Republic. Can't finish the truck, but I'll be back in 10 days, max 2 weeks.

Problem is, I just got back from the South of the Netherlands with the new filters. Did not have time to replace them, did not have time to flush and clean the fuel tank, don't have new oil or fuel yet.

Potential problem: fuel filter housings have been removed so the lines are open to the air. Its very damp and misty here in the mornings, and rainy season started (thinking of rust and water damp in the lines). Can I just leave it for the moment or should I spend precious time on somehow protecting it; I don't really have time anymore to reinstall and run it properly before I leave.

 

[Robo McDuff]

OK, back in the Netherlands and started to do something.

For the engine, I just bought a straight simple 15W-40.

Spent the whole tuesday driving and thinking 5-ton tricks and treats. After going crazy about all tranmission oil threads, especially about Dana - Spicer not liking GL5 oils, I looked again at numerous sites (both SS and outside) and talked with the truck supply guys here.

I finally decided on a 80W-90 GL-3/4/5 gear oil. This oil satisfies the following specs:
- API GL 3/4/5 and MT-1
- Mil-L 2105 B/C/D/E
- Mil-PRF-2105E
- SAE J2360
- and special other truck specifications.

Bad side: it's 1.5 Eur pre VAT more expansive than the one originally planned on.. Ouch.. ( we need a real crying smily).

So 30 liters transmission oil sets me back 177 EUR (or $ 243). Add $ 60 for the 15W-40. Hydraulic oil I can buy only in 20 l ( 5.5 gallon), setting me back another $ 120 (but I'll have 10 liter spare).

More later on the oil changes and cleaning stuff.