Trans oil for AC 10w

I did a little research on this new oil for my tranny on the HD7g. The Champion brand 10 wt. from our tractor store is rated CS and Allison C3/C4. This oil should replace the C1 or "10W crankcase oil" as stated in my AC trans. manual. If I'm wrong, anyone, please correct me . In my shop here it's 30 degrees, and this stuff is as thin as hot bacon grease. I can feel the flow!

Thanks, Steve, your confidence is most reassuring. Turns out the good fluid is little more expensive (33$ for 2.5 gal) than ATF.  Regards, c.

  Well, finally got that screen out; it had a lot of junk on it, and the cavity in which it sits was just full of all kinds of crap, including large pieces of gaskets, probably from an old brake or clutch change. I cleaned the thing with diesel and a bronze wire brush, and put it back in. It didn't appreciably raise my tranny pressure readings, but did wonders for the steering system, now able to turn easily at lower power settings. I then blocked off the speed governor main feed, and the push=start line to isolate the trans pump from any possible fluid diversions. No help. I then removed the trans selector valve and took it home for inspection, man that thing is hard to get to!                           Upon inspection, the trans lube relief spring is noticibly weaker that the new one I got from minnpar, although the free length is OK. The main (apply) spring is very short, with (4) 1/4" washers under it. As I said before, the lube and main pressures are just adequate at high idle, hot, but drop off greatly at low idle. My low idle may be set too low, too, and the pump may need more speed to keep up. With the push=start pump engaged, the pressure maintains much better at low engine speed, but the pressures, especially the lube, never really get deep into the green. That's why I suspected that this is a problem with pump volume.......... I think I have a worn pump, weak relief springs, and unrealistic expectations! HAH. Anyway, now I'll know for sure that the reliefs are set right, and I can address the pump issue at my leisure if necessary. I would just think that big ol pump should be able to provide enough volume to keep these pressures up, even at low speed.     Oh, yeah, the AC manual calls for 10-15 psi on lube pressure, but the gauge is in the green range from 5 to 15 PSI? Should I just be happy with green?  Manual also show a drastic difference in torque convertor pressure settings, early 5+ lb and late, 9 + lb. That's a lot of difference, anyone know why the change?   All the pressure readings call for high idle, hot oil, but when you're working the tractor hard, you're not always going to be at full throttle, except when pushing dirt or trees.  I'm certainly getting an education here. Anyway appreciate all your help. Corey

HD6 Merv wrote:   Well, Merv, on your tractor, what do your lube and main readings(tractor dash gauges) read at hot low idle? When I'm descending a steep hill with a loaded bucket, I'm at very low rpm, and can't speed up safely to keep this pump cranking. I'm just trying to find out if I'm chasing my tail. Hi Corey, good to see you had success with the 7.  Torque converter inlet pressure should be 35-45 psi. This is taken from a T put into the supply line before the converter. There is also a small inline filter to check on the return line to the trans. is a small housing below Lh brake pedal about 2 inchs long; 1 1/2 in diameter, just a small screen, check its not clogged. a good hyd shop should be able to bench test your trans pump. Front section is only a scavenge pump, rear section is pressure. specs for early pump are 5gpm at 1200rpm at 160 psi oil temp 200f. my book doesnt list specs for later pump. Cheers merv

    Well I got back down there to the old 7G and reinstalled the tranny control valve. I also replaced the main battery cable to starter as mice or chipmunks had nearly chewed it in half under the seat long ago and stripped nearly all the insulation. Upon restarting the machine, I realized a slight increase in lube pressure and a little more solid engagement in the gears, but when the fluid got warmed up, the pressures still dropped off drastically. I wanted to remove the trans pump then, but the little voice in my head kept telling me to install that shiny new trans strainer I bought last week. 81 dollars from Minnpar. I just kept thinking that old screen that I cleaned and cleaned still had debris in the pleats that can't be fully flushed. After I had first cleaned the strainer, my steering system began to work better than ever, but my trans pressures were still low when hot at low engine RPM. So, I crawled back under there and put the new strainer in.                                                      The results were very encouraging! Not only are my pressures better (12 lb lube, 180 main) but now they maintain green zone readings at or near low idle speed. I don't doubt that my pump is tired, but the slightest compromise in the supply side really affects it adversly. The steering pump is probably stronger, and was able to dominate the available volume of fluid passing the strainer. So I think I've got this problem licked.      

  The new strainer fit correctly, one minor difference was, the threaded nipple was either slightly shorter or cut threads cut a little deeper. I sealed the threads with a little bit of oil resistant silicone, and also between the strainer cup and the strainer housing. It threads in a little deeper, but might be an improvement as now the filter can't "rock" around. My old strainer was kind of floppy. It was number 70623268.  Minnpar said they sell 6-8 of those per year, and although they had this one in stock, they need a couple of weeks to restock these. I think it's money well spent. It was strange that my transmission always worked great, but the steering system was balky. Now it's all good. Having two of three pumps sucking off the same "tit" can make diagnosis difficult. I did a bunch of looking at aftermarket pumps, and I'm sure I can replace that tired pump eventually with one that's suitable. Thanks again for your help. Corey