Do I have a big problem with my TC40DA

[Laminarman]

I have a TC40DA HST and have loved it so far. Just turned 400 hours, all service has been performed. Recently I thought I heard a "ticking" sound a few times, but ONLY in 2 WD mode, never 4 wheel. Called my dealer and they said to check to make sure the differential lock was dis-engaged. It would not budge, when I step on it, it does nothing, the pin does not pull out of the transmission or whatever that is. Called them back, they said to do the simple first, keep greasing her up there with a penetrant and try to free it, and I have done that ad nauseum and won't budge. Today, of course the holiday weekend, I noticed that when in 2 WD I'm running ALL 4 WHEELS in 4WD mode! She doesn't seem to engage to 2WD at all. What the heck gives? Being the typical tractor head, but under-knowledged, it's gonna KILL me to wait to Tuesday when the dealer opens back up and I'm sure they're just gonna come pick it up ($100 each way just for transport). Thanks.

 

[radman1]

Trace the linkage from the 4wd engagement lever to the transmission. Make sure nothing is disconnected. Then check to see if there is a way to adjust the linkage. Look for someplace with threads and locking nut. If you find it, try to readjust the linkage. From you description, it seems like it is not disengaging completely.

 

[FULLPULL]

Check to see if the lever is twisted between the slot it rides on my old tc40d 4x4 lever twisted and wouldnt move . I took a cresant wrench and lined it with the slot and it worked fine. The metal is soft on that lever for some reason and easy to bend if trying to force into 4x4 mode.

 

[Laminarman]

Fullpull, yes my lever also is twisted and bent. A prior service call had the following mechanic's notes "twisted engagement lever, common problem". Yes, mine bent but this is different. I'll check the adjustable link and the path of that lever in the morning. Thanks again.

 

[jinman]

Differential lock and 4WD engagement are completely unrelated. 4WD is an engagement in the transmission, not even near the differential. Differential lock occurs far behind the transmission. Also our tractors do not have true 4wd. The front differential has no differential lock as the rear does. One of the front wheels will slip if it does not have the traction of the other wheel.

Your 4wd lever may be bent and you may be staying engaged all the time, but it has nothing to do with the diff-lock. If you have a helper, you can view the lever and rods moving by looking in from the rear of the tractor between the wheel and the transmission case and having someone move the lever from engage to disengage. If your lever has full motion between the lock indents, I think it indicates free motion of the mechanism. I know it is not easy to tell if you are in 2wd or 4wd unless you are in load or pulling up a hill with a full FEL bucket. How did you determine you were stucik in 4wd? Just curious...

You may know all this, so if I'm repeating a known fact, I apologize. The differential lock is a pretty simple mechanism, kinda crude actually. When you step on the pedal, you force a differential lock clutch with four fingers, to engage a differntial lock gearcase. Those four fingers essentially lock the two rear axles into a single axle so that both rear wheels must turn all the time. There is a spring to disengage the lock. This is supposed to occur when there is not enough rotational torque to hold the fingers engaged. Therefore, if you lift your foot off the lever, when differential lock is no longer needed, it automatically disengages. If your lock is not fully disengaging, the fingers may be rubbing and causing the clicking. I would think this is not good because the fingers are not supposed to be in constant contact. If the fingers are fully engaged and won't release, it could be that one of the fingers is burred and it is stuck so the spring cannot force it to release.

I hope you get your problems fixed soon and it doesn't cost an arm and leg. Transportation costs are something that cannot be recouped. They are just overhead to having service performed at the dealer. Good luck.

 

[Laminarman]

Thanks Jinman. I found out it was stuck in 4WD when I was loading some dirt in the bucket. I put it in 2WD since I had to make very, very tight turns after picking up the load, and when pushing into the pile, the front tires were spinning and grabbing, spinning and grabbing on the gravel the machine was on, as were the rear wheels. It was then that it seemed the throw from 2 to 4 WD was easy as butter and almost like I was not engaging anything. Yeah, I don't like the sounds of things as they are.