3-Point Hitch 3pt draft arm broken-3720

[AKfish]

Can anybody confirm the comparative strength between the telescoping and std arms?

They've got to be designed to the same specs as the standard lift arms - at the very least. Or, failures and replacement would become an issue.

And the manufacturer would either redesign or stop offering the option.

AKfish

 

[JB4310]

They've got to be designed to the same specs as the standard lift arms - at the very least. Or, failures and replacement would become an issue.

And the manufacturer would either redesign or stop offering the option.

AKfish

Along these lines, check and see if those telescopic ones speced for your machine are the same ones used on higher capacity machines, if not, then they're probably just made to be equal to the stock part.

If same part number for for higher capacity tractor, then they would be made to those higher specs.

JB.

 

[jenkinsph]

I just went out to the shop and compared the stock arms to the optional telescopic arms. I found them to be very similar in dimensions and strength. Simply put I think you had back luck and got a defective arm. The arms are the same on the the 110 and 4xz0 tractors and I would expect all the 3x20 series would be similar to each other.

While it is unfortunate to have this problem I would buy the pair of telescopic links and move on. They are handy to have and I have the IMatch too.

 

[Spudland_Dave]

Telescopic Arms + Welder = Non Telescopic arms Sorry, but I had to say it...

Just an option...dunno your skill level & desire to tinker, but why not just build yourself a new arm to match the one you broke? Could probably build one yourself for $25.00

 

[turbo36]

KennedyDiesel, I bought the telescoping arms for my 3720 after it was delivered and the dealer told me to keep my old arms because he didn't want them and thus would not offer a trade-in value. I'm sure I have them in the polebarn, the problem is it's a 6 hour round trip and I won't de able to get there for a couple of weeks.

 

[Deerescaper]

Don't feel bad about your draft arm as I've broken six of them in 1600 hours on my 3720. Warranty covered the first one and we've bought a couple spares since. Also have welded them when they broke in the hole such as yours with gussets on top and bottom both. Broke one last Sunday ahead of the hole by where the sway bar attaches. That was the first one of the welded ones that broke. 85% new break and 15% previous stress cracking.Load on it at the time of breakage was 5 foot snowblower pushing snow with the loader,not even blowing at the time. I have broken them with a tr3 rake on as that is a heavy unit (6') and my 5.5' rototiller. Bitched to John Deere dealer that they are not heavy made enough and his answer was must be using it to hard. I bought the tractor to do landscaping work with not to sit on the lawn and look pretty.I don't baby it or do I abuse it but I feel the arm design should be more like the old 4020 or 4430 which does not have a hole drilled directly through the arm but attaches to a casting with the arm forged below it.
Seems like the only weak place on the whole tractor/loader setup in my experience. Unit is a 2006 and I will check on the adjustable arms at my dealer when I run out of room to weld on these.

 

[KennedyDiesel]

Don't feel bad about your draft arm as I've broken six of them in 1600 hours on my 3720. Warranty covered the first one and we've bought a couple spares since. Also have welded them when they broke in the hole such as yours with gussets on top and bottom both. Broke one last Sunday ahead of the hole by where the sway bar attaches. That was the first one of the welded ones that broke. 85% new break and 15% previous stress cracking.Load on it at the time of breakage was 5 foot snowblower pushing snow with the loader,not even blowing at the time. I have broken them with a tr3 rake on as that is a heavy unit (6') and my 5.5' rototiller. Bitched to John Deere dealer that they are not heavy made enough and his answer was must be using it to hard. I bought the tractor to do landscaping work with not to sit on the lawn and look pretty.I don't baby it or do I abuse it but I feel the arm design should be more like the old 4020 or 4430 which does not have a hole drilled directly through the arm but attaches to a casting with the arm forged below it.
Seems like the only weak place on the whole tractor/loader setup in my experience. Unit is a 2006 and I will check on the adjustable arms at my dealer when I run out of room to weld on these.

Have you looked at the new ones? They are defintely different on the new models. I'm wondering if this change was to address this?

Buddy has a new 4720 (replaced lemoned 4320) and says that his new one has different arms.

I ordered the telescoping units for now. Eventually I plan to trade in for a new one, but depends on the economy.

 

[JB4310]

Don't feel bad about your draft arm as I've broken six of them in 1600 hours on my 3720....
I feel the arm design should be more like the old 4020 or 4430 which does not have a hole drilled directly through the arm but attaches to a casting with the arm forged below it.

If you are repairing them yourself why not make them like that, with the attachment above the arm, eliminating the hole in the arm.
I was gonna recommend that to KD but it seemed like he wasn't interested in repairing his.

I did ever so slightly bend mine on my 4310, but that was from beating them with a rear snow plow pushing backwards, ramming snow banks. I straightened them and added a 3/4x1 inch bar under the factory bend and hole area, so that added 50% of the stock arm.

6 broken arms, that's definetly a poor design/construction.
I'd gather them all up and bring them to dealer, drop them on the parts counter and start ringing that bell, annoyingly until I got everyone's attention

JB.

 

[sunnyside360]

Buddy has a new 4720 (replaced lemoned 4320) and says that his new one has different arms.

Interesting!! Did your buddy get any help from the dealer and/or John Deere on the trade?? I know a guy (neighbor) who thinks he has a lemon 4320 and is thinking about trading for either a 4520 or 4720? He's had quite a few issues and it only has about 100 hrs on it.

 

[KennedyDiesel]

Interesting!! Did your buddy get any help from the dealer and/or John Deere on the trade?? I know a guy (neighbor) who thinks he has a lemon 4320 and is thinking about trading for either a 4520 or 4720? He's had quite a few issues and it only has about 100 hrs on it.

I don't want to take this too far off topic so if you have any more comment please PM me.

I believe it was a 4120 now that I think about it, but word is the 41 and 43 fuel systems tended to be more problematic than the 45 and 47. I was there the day it started missing for the first time. He was working on our land with the backhoe and it just became a 3 popper. It was still bright, shiny and new. He had it in numerous times and it kept diluting the oil with fuel. They tried and tried again. He even offered to have them swap the engine, but they wouldn't so he went for a new 4720. He's REALLY happy so far with this one and the E-throttle and E-PTO etc. Lots of subtle changes since his early model and gobs more power.

Deere wasn't too impressed when he told them that I had originally warned him against buying it due to the Stanadyne fuel system...

 

[KennedyDiesel]

Here's a pic of the broken link.

 

[Deerescaper]

Here's a picture of my broken arm. This one had already broken and been welded at the pin hole. As you can see it it not a completely fresh break with the rust evident on the rest. I went by the local dealer but they didn't have any 3000 series on hand so couldn't compare to the newer style.

 

[JB4310]

Man both of those look like some pretty crappy China smelting pot metal castings.
They use to use that junk for the old window weights.

Definitely not something to build a critical strength application part on a high end tractor with.

I'd probably still just weld em back together, if replacements weren't any better or very expensive.

JB.

 

[Spudland_Dave]

I'm guessing this is a "known issue"
I didnt "break" mine clean in half, but within 15 hours of getting my 3520 I had one arm bent like a taco....thought for sure I would have had to buy one, but for grins I talked to the svc manager about what happened, and without batting an eye he said they would warranty. I got the feeling it wasnt the first one, and with this post I'd say my suspicions were true.

 

[KennedyDiesel]

I did a quick weight count on the early arm vs the late model replacement. The early is a more rounded bar and the late is more squared. The early was like 14.5-15# and the late is 16-16.5#

Teh telescoping arms are about 18@ but are basically the early arms with the telescoping end.

I also had to choose different sway pin positions in order to get my Imatch centered. It seemed as if the early arms may have been slightly bent where the lift link holes are located.

 

[AKfish]

From the dark, shaded area it appears to be a defective casting. The rust appears to have spread outward from that -- and then you just plain broke the rest of it!!!

I don't recall or not if your dealer offered to cover everything under warranty (or just good customer relations) or if you had to cover the expense.

Glad to hear the new design is heavier duty.

AKfish

 

[Deerescaper]

You know when comparing the pictures I'm not so sure mine isn't the newer style as it looks to be more square than the other fellows. Still a pain when it happens and the dealer only warranteed one arm for me and I've bought two others at my expense. I am going to talk to a regional block man about this problem as local dealer made it sound as an isolated case. Glad to hear I'm not the only one breaking the pot metal.

 

[KennedyDiesel]

Just a follow up here. This weekend I got a little rough with my skidding winch and made a mess of my 3pt. This was with the telescoping links which are the only reasonably priced units out there. I ended up bending the RH draft link up like a pretzel, BUT it did not break or even give the appearance of beginning to crack. The fork for the lift link broke, but that is because it received a heck of a spreading force.

I recently had the LH lift link split on me so I replaced it with the much heavier later unit and am now replacing the RH unit with the later one.

I should add that this recent issue is purely me being too rough on things. The failure of the original draft arm I chalk up to cheap crappy steel. The failure of the lift link I chalk up to undersized spindly design. Looks like this has all been corrected in the later models...

 

[JB4310]

By their design and intended use they should be able to take a beating with out this much drama.
I did bend mine, but that was from ramming snow banks in reverse with a modded truck plow mounted to imatch.

Most would say not an intended use for 3 pt

JB

 

[Deere Dude]

I bent one on a 3720 because I had a loaded bucket and backing into a fairly loose pile of dirt with a dirt scoop. I was backing in 4WD and raising the scoop as I was backing it in to get a bigger pile on it. It was a 30 hour tractor so I took it to the dealer and the replaced it free and not a whole lot was said about abuse. But just enough to where if it bends again, forget it.
I thought they make them out of cheap steel. Anyway, I was very careful after that and then last summer I was clearing brush with the FEL and accidentally backed into a 5" diameter tree and bent the same one again. I hardly felt much of a jolt. This time I just put it in the log-splitter and straightened it and got it fairly straight. I still don't trust them very much anymore. It must be to much horsepower because I remember a Ford 8n ripping it to er' in reverse moving all kinds of dirt.
Way at the beginning of this post someone welded a bar on the top of theirs so maybe I'll have to do that. Of course I would hate to have a piece of cast break off the trans-axle either.