I just happened to read this thread by coincidence today. Although, Western plows do take ATF fluid I had an interesting experience with my Western today. I use ATF in some of the other Westerns we have, but there's one plow that's been a headache for 2 years now. It's been drawing too much on the electrical system. I've done a lot of troubleshooting and reapirs to correct the problem - some made a difference, some didn't. Anyhow, I went to move the plow (and the truck) today and the plow ran but no action (up/down -side). A quick check revealed that the ATF in the plow was milky and thick - sure sign of water in the system. After I drained and flushed the system with kerosene, I decided to splurge and spend the $5 a quart for the high -end plow fluid that's rated to -40. You can definitely tell the difference in viscosity between tranny fluid and this stuff - plow operates much faster/less drain on the system.
I've always been told that the good aircraft grade hydro fluid is worth it. We use it in a lot of the Meyer pumps we have but tranny fluid has always been a good standby in the middle of the night and will work fine in most situations. Long story short: If you're gonna be using the plow in cold conditions (below 10-15 degrees) and you don't have a system leak that requires you to refill frequently, you might want to consider spending the extra $2-3 for the good stuff - but if not, the ATF will probably do you just fine. Good Luck Sorry for the long post, just thought I'd impart some of my past experience for ya.
Western now solely uses there high performance fluid on all uni-mounts and ultra-mounts. if youre getting atf with youre new plow,youre getting hosed. good luck #1 PT. (p.s. they you to buy there stuff so they can be even more rich!!)
Bridges - I've spent the better part of two years tracking down a similar problem. New Batteries, New alternators, new pump motors, new pumps, etc.....
My best advice is to get the Western repair manual from JThomas Distributors (about $15) and go through the trouble shooting guide. It's an excellent resource and will help pinpoint your particular problem.
I'd start by testing the draw on your pump motor (electrical) and make sure it's within the amp range. If it is, the problem lies in your alterantor or battery. If it's not (too high a draw), it lies within the pump side.
First check the hydro pressure output (I think it should be around 3000 lbs). If that's low, see if you can adjust the pressure relief on the pump in increase it (and while you're at it, change/clean the filter as this can easily cause the system to run hard and drain amps). If the motor, pump and filter all check out, flush the system with kerosene and refill it with the premium fluid. If this still fails, my guess would be that it's one of the O-rings in the valve body/crossover. One of these 5 cent O-rings can make your life hell if they wear out. If you're the least bit mechanically inclined, all of this is pretty easy to do. The manual will help out a lot though. I hope all this helps - don't feel bad, I spent nearly $1,200 tracking down this problem last year (with bad mechanics that just replaced parts and treated the symptons instead of the cause). I finally got a break from plowing and tore into it myself - only to find that it WAS a 5 cent O-ring!!! Had the mechanic that I brought it to originally done a pressure test, he would have known this right away (he said he did the test and replaced the motor instead). Good luck - need more advice, write back.
That would be my guess. If it is not in "float" position then it could still have pressure on it. Float is so there is no pressure on the ram (piston) and the blade can float along with the contours of the surface you are plowing.