2520 popping out of 4WD

[Gobblin Tom]

I got my tractor back and so far so good. It hasn't popped out of 4wd since I got it back this most recent time. I talked to the mechanic and he said that he replaced a part called a "button". Aparently that part pushes against the detent. He said that he saw some issues with it that he didn't see the first time he took it apart. The good news is that he didn't have to split the tractor to replace, he was able to replace it by just taking off the side cover of the transmission where the 4wd shifter goes in. Maybe the new "button" and/or the tire pressure changes have solved the problem. I'm keeping my fingers crossed.

Let me know when you give it a good test with some good weight in the bucket going down hill... If you can PM me your dealers name so I can call and find out what the part is actually called. Also did they give you a reason why it failed? I hope you and they are right and it fixes the 4wd!!

 

[ZR7400]

I did try the tractor with a heaping bucket of #2 gravel in the same area where I could consistently get it to pop out of 4wd before. It did not pop out this time. I will have time this weekend to use the tractor more and give it a better test. As far as the part that was replaced they told me that John Deere calls the part a "Button", so I guess that is the official name. The mechanic did not say what was exactly wrong with the button or why it failed, but he did say that he saw some issues with the button so he went a head and replaced it.

Tom, Just a thought before you send your tractor in you might want to adjust the tire pressures like the dealer did to mine. They put 32psi in the front and 10psi in the rear tires. John Deeres thought is that it will change the gear ratio slightly between the front and back reducing the possiblity of kick out under high stress situations. They did this to mine along with replacing the "button". I wasn't able to test the tractor after the tire pressure change so I can't say with any certainty that the solution is one or the other. They had to lay the tires flat on the floor with valve stems up to release the air pressure because my tires are loaded with Rim Guard.

 

[Gobblin Tom]

I did try the tractor with a heaping bucket of #2 gravel in the same area where I could consistently get it to pop out of 4wd before. It did not pop out this time. I will have time this weekend to use the tractor more and give it a better test. As far as the part that was replaced they told me that John Deere calls the part a "Button", so I guess that is the official name. The mechanic did not say what was exactly wrong with the button or why it failed, but he did say that he saw some issues with the button so he went a head and replaced it.

Tom, Just a thought before you send your tractor in you might want to adjust the tire pressures like the dealer did to mine. They put 32psi in the front and 10psi in the rear tires. John Deeres thought is that it will change the gear ratio slightly between the front and back reducing the possiblity of kick out under high stress situations. They did this to mine along with replacing the "button". I wasn't able to test the tractor after the tire pressure change so I can't say with any certainty that the solution is one or the other. They had to lay the tires flat on the floor with valve stems up to release the air pressure because my tires are loaded with Rim Guard.

Let me know after you give it a good test this weekend! I also have rimguard but I don't think I will loose a whole lot as long as I have the valve stems up. Right now I don't have much faith in where I bought my tractor, they said my saw was fixed and its not, now it is at another stihl dealer. I have called and left messages and emailed several times about my rear chains that were supposed to be put on when I bought it and have got no answer back, they kept telling me they weren't in stock... Luckily there is another JD dealer closer to my house and I can see if they could do the 4wd work. I didn't buy from them originally because they wanted around $2500 more for the same tractor. I am starting to get mad about the chains!!! Winter is on its way and I am going to need them for my driveway...

 

[Gobblin Tom]

Does anyone have a schematic they can post on here to see what this button is?

 

[PCABE5]

Does anyone have a schematic they can post on here to see what this button is?

No button in the repair manual. ZR7400 said that they removed this section so the part should be in this section.

The air pressure sure sounds like someone fishing for an excuse. Remember the front to rear ratio is already 1.538 which is set by gearing and the loaded radius is not going to change significantly to cause an issue (unless you run your tractor with the front tires flat). But even with that said the ratio front to back when considering tire combinations has a "window" of acceptability and not a set standard to compensate for manufacturing differences in tires.

John Deere - Parts Catalog

 

[Gobblin Tom]

No button in the repair manual. ZR7400 said that they removed this section so the part should be in this section.

The air pressure sure sounds like someone fishing for an excuse. Remember the front to rear ratio is already 1.538 which is set by gearing and the loaded radius is not going to change significantly to cause an issue (unless you run your tractor with the front tires flat). But even with that said the ratio front to back when considering tire combinations has a "window" of acceptability and not a set standard to compensate for manufacturing differences in tires.

John Deere - Parts Catalog

That's why I would like to call his dealer and find out exactly what it was?? I agree with you on the tire thing, it shouldn't matter if they are flat, over or under inflated still no reason to disengage the 4wd! I am waiting to hear about his time on the tractor this weekend to hear if it is fixed.....

 

[glc24]

Hey Tom
Here is the parts breakdown.I wonder if it's the item listed as #7.
It's listed as a ball,and there are two.
Maybe that spring between them is too weak.Who knows.
There is no part listed as a "button" though.

Greg

 

[Gobblin Tom]

Hey Tom
Here is the parts breakdown.I wonder if it's the item listed as #7.
It's listed as a ball,and there are two.
Maybe that spring between them is too weak.Who knows.
There is no part listed as a "button" though.

Greg

Yeah that definitely don't show a button? Hopefully ZR7400 chimes in on all of this...

 

[PCABE5]

Hey Tom
Here is the parts breakdown.I wonder if it's the item listed as #7.
It's listed as a ball,and there are two.
Maybe that spring between them is too weak.Who knows.
There is no part listed as a "button" though.

Greg

Thanks Greg, that was the picture I tried to post as a link but obviously my link did nothing.:laughing:

I wonder if you can get to #7 by just removing the side plate. The repair manual does say to be careful with these on assembly as they can come loose.

ZR7400 had said, "The 4wd lever now goes clear to the floor board and there is no longer any detent clicks, just a smooth glide from the the 2wd position to the floor."

So I would guess that the lever was no longer engaging the collar (#11 and #12). If I were to continue to guess, the button was #11 and was either missing or not placed back into the collar and that is what allowed the lever to move freely. Like I said just a guess since 4wd did not work at all.

 

[ZR7400]

I'm now wondering what my mechanic was talking about. I agree that there is no part called a "button" on the diagram. I'm starting to think that it was the balls. I asked him twice and he said button but I will find out and settle this.