Hill problems

[yanmars]

I have a manual front wheel assist Mahindra 4510 tractor. About 45 hp. When I am in 4 wheel drive going down a hill it wants to "freewheel" and gain so much speed the brakes will not hold it and I have to put the front end loader bucket down to slow it down so it does not get out of control. I am NOT pushing the clutch in.
The other problem, going uphill I barely have enough power/traction to get up the hill unless I also engage the rear wheel lock so both rears are locked and pulling. This is a recent occurrence, it never did this in the past.
The rear tires are over 60% and the fronts are slightly under 50%.
Any thoughts as to the problem? Thanks

 

[Oldmopar]

I'm not sure about what is wrong with your tractor, just a guess, your clutch maybe going out or out of adjustment. But please be dambed carefull lowering your bucket going down hill! I can see all sorts of bad things happening, from flipping the tractor to tearing off the loader or much worse.

 

[Gordon Gould]

More detailed info will help.
Is it a power/engine braking problem like a badly slipping clutch (smell it burn ?) or super low compression (very hard to start ?). Can you hear engine reving up going down hill ?
Or is it a traction problem where it slides down hill and wheels slip going uphill?
Is you 4wd working correctly ?

 

[alchemysa]

Do you have a high/low range selector? Your uphill and downhill problems sound exactly like its in high range.

 

[MHarryE]

Since this is a recent problem is it possible you have had a failure in the rear diff? The diff lock could be powering around the failed component. I am not sure how the diff lock on your tractor works - there are different designs. I assume everything works okay when in 2 wheel drive so that rules out a completely failed drive train to one rear - the tractor would just sit there and not move. Another thing I was thinking of since you said this just started is something in the front wheel drive that is causing drag but that would not explain the loss of braking.

 

[yanmars]

I had a new clutch and throw out bearing put in about 30 hours ago. This problem did not arise until I had it at the dealership after the new clutch and they had it for over 9 weeks and put 14 hours on the tractor. I am not sure what all the hours were for but I noticed the problem very soon after I had it back.
I am not saying it was related to that but that is when it occurred first. They cleaned the radiator, put in a thermostat, hoses, new coolant and a battery.
I do not hear any overrevving etc.
I "thought" it could be a clutch but that is so new but who knows.

 

[Don87]

I had a new clutch and throw out bearing put in about 30 hours ago. This problem did not arise until I had it at the dealership after the new clutch and they had it for over 9 weeks and put 14 hours on the tractor. I am not sure what all the hours were for but I noticed the problem very soon after I had it back.
I am not saying it was related to that but that is when it occurred first. They cleaned the radiator, put in a thermostat, hoses, new coolant and a battery.
I do not hear any overrevving etc.
I "thought" it could be a clutch but that is so new but who knows.

The clutch can be new, but still do what you describe if it is slipping.

Have you checked to see if the 4WD is operating correctly?

 

[k0ua]

A slipping clutch explains everything except why pressing the differential lock helps get up the hill. That I haven't got figured out . Are you sure it really helps? Is one tire spinning going up the hill? This part just doesnt make sense to me.

James K0UA

 

[bcp]

If a rear axle gear or shaft was broken/stripped, it could have similar symptoms. 4WD position would really be 2WD until the differential lock was used. When climbing, the rear power goes to the nonfunctional side until the lock is used.

You didn't mention what happens in 2WD.

Bruce

 

[MHarryE]

I couldn't figure out how using the diff lock would help if the problem was a slipping clutch. Logic would say it would make it worse. Example with my hydro - if I am in a condition where I need to use the diff lock, it lugs the engine down because of the extra power now being transmitted to a wheel that has traction. And if a clutch could transmit enough power to enable climbing a hill, why would it slip to the point of free wheeling on the way down? Why aren't all problems as easy to diagnose as, " Engine started to make noise so shut it down. Looked up front and there was a hole in the block and a bunch of parts mixed into a large pool of oil on the ground."