Hello. My name is James and I've been looking for some information concerning hydraulic fluids. Other than a 58 Ford 800 tractor I don't own any heavy equipment but I do have a piece of equipment that requires a hydraulic fluid. The reason I was wanting some German input was the car in question is an East German built 1981 Trabant 601. Here are some pics: http://s222.photobucket.com/user/turbofiat/library/Trabant?sort=6&page=1 The jest of it. The gearbox is supposed to use a hydraulic oil called HLP 68. HLP must be a German or European designation because it doesn't exist in the United States. I finally cross referenced this oil to a Citgo Mystik ISO VG 68 from Tractor Supply. Both are a mineral oil and contain a zinc anti wear compounds according to the MSDS. There is also a Mobil DTE 26 or something but it's only available in 5 gallon buckets. I'm having some issues with the operation of the Sprag clutch (which is basically a one directional bearing) in cold weather. This device goes between the input shaft and 4th gear and acts as a freewheel device to prevent the driver from using the engine as a brake going down hills (because the engine is a 2 stroker). No doubt the device probably has some wear on it but I found if I use a thinner oil like Mercon or Dextron it works better. For whatever reason works 0W20 is horrible! By all accounts this stuff should work better in cold weather. I've done several diesel fuel flushes trying to flushing any junk out of the gearbox by running diesel fuel just up the road and back and with diesel fuel the device works flawless but diesel is not a lubricant so I don't want to use it as a lube. It seems flushing the gearbox out seems to help. I tried the AW 68 and it works OK at 50F but right now I am using a multi-weight hydraulic oil I got from Tractor Supply which seems to work better. Even better than Dextron or Mercon ATF. But what I want to know is can I use an AW ISO 22? I'd like to use the thinnest oil possible but still provide enough protection. I found these charts: I went up the road for about 5 miles with the AW 32/46/68 and aimed an infrared heat pen at the gearbox and measured around 110F. Does that mean I could get buy with an VG 22 based on the charts above? AMSOIL's multiweight hydraulic oil is supposed to cover down to a VG 22 but at $160 for a 5 gallon bucket, it's a little pricey since my transmission only requires 1.5 liters. This test was done at 50F so if I wanted to estimate the gearbox's temperature in the middle of summer (95F) should I add 50F to that? Or should I do this test in the summer? Thanks!
Hi turbofiat . That's a cool car you are working on . You mentioned it had a two cycle . Is it similar to a Rotax ? I think they had beginnings in Austria or Germany . Sounds like you have already experimented with different oil's . If the hydro oil from Tractor supply seems to be working I would probably stay with it . We buy all Hydro oil from either Rural King or Tractor Supply . Put it in everything from the lawn mower , farm tractors , construction equipment . Use some super trac 303 http://www.tractorsupply.com/en/store/xtremereg;-tractor-hydraulic--transmission-fluid-2-gal I like the Xtreme Pure flow a little better . I don't get to hung up over brands & viscosities . In my experience the most important thing is that the engine, gearbox or transmission has something slick in it . Dad came in the other day with tractor & bush hog .............. ( Hey son )........... I think the gear box on the mower has locked up ? Dad ....... Did you check the oil level in the mower before you started ? Total silence ...... LOL ! Not to big of a job , got by replacing bearings & seals .
I can see why you would like to try Amsoil with it having a high VI but use caution. PAO the synthetic base oil Amsoil uses is a great base oil however PAO's work as a solvent as well as a lubricant. It could clean up the waxy build up in the transmission and expose seals. Try a good multi-visc tractor fluid. Tractor fluid is like an AW but with a friction modifier to accommodate clutches.
DIN HLP 68 is a specification for a industrial type of hydraulic oil. The H stands for "hydraulic", the L for "long life" meaning it contains a antioxidant and P stands for "antiwear type" meaning it usually meets the FZG 12 load stage requirements. It is thus a hydraulic oil that contains a antixoidant and a AW-additive. 68 is a indication of the viscosity within the ISO VG system: 68 mm2/s (cSt) plus or minus 10%. since these types of oils have a viscosity index of around 100 it may well get a little too viscous when used in cold weather. there are two ways to get around this: either switch to a lower viscosity oil (HLP 46, or even 32) or use a "multigrade type oil like a SAE 5W-30 or 10W-30. A ATF more or less resembles a SAE 5W-20 oil but might be a little too thin when the oil gets warm.