1991 champion 740 Grader feels clutch sliping or something else please help asap

1991 champion 740 feels clutch slipping. I am new to graders this is first grader I bought in my life. It shifts all forward 8 gears but after shifting to higher gears rpm's goes higher feels cluch slipping and it is not moving as it needs to be. Up to 7 gears it is bit fine going on but if I shift 8 it seems no power even on minor hill if it have down hill there is no problem
If there is any equipment mechanic or any handyman here in Edmonton we have most of tools just contact me asap because I need this thing please email me
if anyone repair service and parts manual please email jp_trucking@live.ca
Thanks

I ran a 1990, 730A. It had no power on hills. As I understood it, it was a 4 speed transmission with a high, and low range that gave it 8 speeds. If it slips in 8, it should be slipping in 4. If the main clutch is slipping, it should slip in all gears.

Champion 700 series 8400 transmission There is a service manual on E Bay

There used to be a company in edmonton called jade equipment that dealt with a lot of champ graders. Dont know if they are still around, but I would talk with them as well. Might be able to help.

cuttin edge said:

I ran a 1990, 730A. It had no power on hills. As I understood it, it was a 4 speed transmission with a high, and low range that gave it 8 speeds. If it slips in 8, it should be slipping in 4. If the main clutch is slipping, it should slip in all gears.

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Yes sir I found first 3 gears are ok but after it start dying if it is 8 gear it wont even move and in seventh it iries to move as you lowering gears it is moving looks man clutch is ok but transmission output shaft wont tun diffs as it needs to still tring too figureout whats problem

It does not make sense when I think about it, as that transmission has no internal clutches. Like I said, there is a shop manual on ebay. Good luck

What makes you think the main clutch isn't slipping? Cuttin says it should slip in all gears if it's slipping, which is true but only at the same torque (load). If you're just driving up a hill, then it won't slip in low gear because there's not as much load on the engine/clutch as in high gear at the same slope. You could try pushing a heavy load in a middle gear to see if it slips the same under load.

Yeah, I am in agreement with Delmer. The transmission itself can't slip. It's either in gear or not. Try putting the lower gears under load like he said. If it comes down to it, the clutch is not hard to get at.

That 8400 has 4 clutches, and two of them have more then one position. You get your gears by which combination of those clutches are engaged. It can be a solenoid, the most fussy of which, there are two where there are two coils stacked on one spool. You're going to have to figure out what gears you do or don't have. If you're pretty sure you don't have 7 or 8, my guess is you don't have 3 or 4 either. I don't have the manual handy (I ran them and have had the problems, I'm not a mechanic). Once you know which clutch, it could be the solenoid (cheap and easy), hydraulic circuit (like the collector block, unlikely, but still not a teardown) or the clutch itself (bad news, BUT, the trans does come out of those things in a couple of hours. DEFINITELY talk to JADE. They can help get her back on the road.

Fatgraderman said:

That 8400 has 4 clutches, and two of them have more then one position. You get your gears by which combination of those clutches are engaged. It can be a solenoid, the most fussy of which, there are two where there are two coils stacked on one spool. You're going to have to figure out what gears you do or don't have. If you're pretty sure you don't have 7 or 8, my guess is you don't have 3 or 4 either. I don't have the manual handy (I ran them and have had the problems, I'm not a mechanic). Once you know which clutch, it could be the solenoid (cheap and easy), hydraulic circuit (like the collector block, unlikely, but still not a teardown) or the clutch itself (bad news, BUT, the trans does come out of those things in a couple of hours. DEFINITELY talk to JADE. They can help get her back on the road.

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There you go. I had no idea that the 8400 had internal clutches. I always figured that the solenoids just shifted the gears into different positions. I would talk to the pros like Fatman said. Sorry for the miss information.

They're a hybrid. If I remember correctly (it's been 15 years or so since I've been into a 8400) there 4 clusters, stacked on top of the other, whereas in a typical automatic they're one in front of the other. The clutches are friction and steeles, just like an auto (and the main clutch). They list the 4 clutches as A - D. One engages even/ odd, one evgages 1-4/ 5-8, one selects 1-2/3-4/5-6/7-8, ie pairs. It might be energized for 3-4 and 7-8 but open in 1-2 and 5-6. One engages forward, reverse, and something else I've forgotten. I ran 8 different graders that had that transmission, and they really do have a good track record. The early ones had trouble with the clutch material, but they had so much trouble, they were changed up almost instantly. I have some Ag-mech background, so whenever there were repairs, I washed up parts and such.

cuttin edge said:

There you go. I had no idea that the 8400 had internal clutches. I always figured that the solenoids just shifted the gears into different positions. I would talk to the pros like Fatman said. Sorry for the miss information.

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Like the new autosticks in the trucks. I always wondered if they would eventually go that way. That'd get rid of a hydraulic circuit and a whole bunch of clutches. The old ones we varied the throttle just as you would a standard so the clutches didn't have to slip on each gear change. Sadly, that confuses the power train computer on these new ones, every upshift is under power, and failures seem to be more common.