4WD on a JD6400

roosterman71

Has anyone every experienced the 4WD coming on when you use the brakes? My 6400 is doing it, and the bloody thing won't go off when you release the brakes. The rocker switch is off, and the 4WD indicator light is off. I can get it to release by constantly tapping the brakes when driving but this can't be good.

Anyone every have this trouble?
Or know whats the cause/solution?

marlyman

roosterman71 wrote: »

Has anyone every experienced the 4WD coming on when you use the brakes? My 6400 is doing it, and the bloody thing won't go off when you release the brakes. The rocker switch is off, and the 4WD indicator light is off. I can get it to release by constantly tapping the brakes when driving but this can't be good.

Anyone every have this trouble?
Or know whats the cause/solution?

This is normal operation for this tractor. It ads to the braking power of the engine and rear brakes. The brake switch is ling to the 4 wd switch on the dash. You can bypass this by pulling out the 4wd switch an putting in a flick switch so the 4wd only comes on when you flick the switch.

roosterman71

That doesn't make sense.

The 4WD switch is a rocker switch behind the gears. That switch is off, but after releasing the brakes the 4WD is on, and the switch wouldn't be touched, nor the 4WD indicator light isn't on.

So how would changing the switch help?

Casinoking

Sounds like an electrical problem alright, the 4wd should come on when you press the brakes but it should switch off again when you release them. Could be something as simple as a fuse, I never saw that exact problem before but a phone call to a John Deere dealer should shed some light on it fairly quickly.

scudster

I wouldnt advise bypassing the automatic 4WD braking system. If you need to stop in a hurry on a slippy surface (even a not so slippy surface) with a load behind you, you will soon regret your decision. I had one or two close calls with a JD 6506 with the 4wd braking disconnected. She just slid on down the (dry) road about 30 yards further than I had expected it to. Luckly there was nothing infront of me as I was turning off the road onto a byroad.
I also had a few tight ones on a 2wd ford 6600 with a wrapper behind on a greasy road. Some fun keepin her straight when meetin a car in the middle of the road!:eek:

marlyman

roosterman71 wrote: »

That doesn't make sense.

The 4WD switch is a rocker switch behind the gears. That switch is off, but after releasing the brakes the 4WD is on, and the switch wouldn't be touched, nor the 4WD indicator light isn't on.

So how would changing the switch help?

The 4wd switch and the brake switch are linked. Pull them out and youll see, they'll either be linked directly or through the board. The same thing happend on mf 42/43 models.

It is not safe to do what im proposing, however when doing loader work in the yard etc, its a pain.

Where are you located and i can tell you where to go to get it sorted.

The Nutty M

roosterman71 wrote: »

Has anyone every experienced the 4WD coming on when you use the brakes? My 6400 is doing it, and the bloody thing won't go off when you release the brakes. The rocker switch is off, and the 4WD indicator light is off. I can get it to release by constantly tapping the brakes when driving but this can't be good.

Anyone every have this trouble?
Or know whats the cause/solution?

May I ask how you know the 4wd is still engaged with no indicator light on the dash?Does the light light up when the 4wd is turned on or when your foot is on the brake?

roosterman71

I know cos the back-end is screaming like there's a small child trapped inside. Same noise as if you had 4WD on and went for a burn down the road. Its a high pitched noise.

I initially thought it was the brakes sticking since it was that kinda noise (when you hit the brakes you hear it). I hadn't realised it was the 4WD linked to the brakes

pajero12

I assume he hears it whining?

The Nutty M

Personally I wouldn't go by the whining off the backend,we've a 6610 and it makes all sorts of weird noises like a bag of cats.The way I'd check it is into A1 and drive,put the foot lightly on the brake and lock hard and come to a stop.Let your foot off the brake and you'll feel if the 4wd unclicks itself.

Good luck with it anyways:)