JD 550G Trunnion Ball / Blade Pivot

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darrenrudolph83
430 crawler
430 crawler
Posts: 55
Joined: Tue Sep 22, 2015 3:41 pm
Location: Alaska

JD 550G Trunnion Ball / Blade Pivot

Post by darrenrudolph83 » Mon Apr 05, 2021 9:22 am

Good morning!

Looking for some info on the 550G trunnion, mine is fairly sloppy and will need to be repaired or replaced soon. I am assuming the ball itself is welded in? Are the balls made of a harder steel then the cap? I am wondering if in general a guy could purchase a new cap, remove any shims if any are installed to tighten up the cap/ball assembly. If the ball is welded in then its going to be difficult for me to do because the machine is located at my remote cabin and unfortunately I do not have a welder capable of a job like that just yet.

Thank you in advance for any help or suggestions on field repairing this well enough for another summers use.

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LeonardL
350 crawler
350 crawler
Posts: 869
Joined: Thu Oct 06, 2011 7:11 pm
Location: Missouri

Re: JD 550G Trunnion Ball / Blade Pivot

Post by LeonardL » Mon Apr 05, 2021 6:21 pm

The balls are replaceable but as you pointed out it isn't an easy task. I have done a few of them over the years and had them removed by our fabrication shop that had air arc equipment to remove the worn ball. The caps are hardened but I have no idea if they are as hard as the ball itself. There are shims that you can remove if haven't done so already. You can add a new cap and tighten the slack up a little but not much. The best fix is to replace all of the pivot mechanism.
40 plus years working on JD 350s, 400Gs, 450s and other equipment both Ag and Construction.

darrenrudolph83
430 crawler
430 crawler
Posts: 55
Joined: Tue Sep 22, 2015 3:41 pm
Location: Alaska

Re: JD 550G Trunnion Ball / Blade Pivot

Post by darrenrudolph83 » Tue Apr 06, 2021 7:04 am

LeonardL wrote:
Mon Apr 05, 2021 6:21 pm
The balls are replaceable but as you pointed out it isn't an easy task. I have done a few of them over the years and had them removed by our fabrication shop that had air arc equipment to remove the worn ball. The caps are hardened but I have no idea if they are as hard as the ball itself. There are shims that you can remove if haven't done so already. You can add a new cap and tighten the slack up a little but not much. The best fix is to replace all of the pivot mechanism.
Thank you LeonardL,

That is what I was afraid of, I suppose the best thing to do will be wait for summer until I am able to get back out to where the dozer and and remove the cap. I am fairly certain from last summer the ball is nearing end of life.

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