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A-arm upgrade

Sheetmetalfab

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If the A-Arms are too strong will the mounting points to the body start breaking? Seems like you want the A-Arm to bend before damaging the bulkhead. What is the goldilocks A-Arm for this? Not too strong but not too weak?
Get the strongest ones you can find.

Nobody makes any strong enough to damage the bulkhead from a ski hit.

Encapsulated ball joints mean 100% of failures are arm replacements.

Alt impact arms are weak.

TREX so far have held up great on the sleds I’ve been around.

I just consider them a wear item and keep a full spare set on hand.

Fancy expensive ones seem to fail just as readily as cheap ones.
 

turboless terry

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If the A-Arms are too strong will the mounting points to the body start breaking? Seems like you want the A-Arm to bend before damaging the bulkhead. What is the goldilocks A-Arm for this? Not too strong but not too weak?
When i was learning to trowel and rake concrete my boss used to say, not too much and not too little. There's a spot in the middle called just right.
 

Teth-Air

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If the A-Arms are too strong will the mounting points to the body start breaking? Seems like you want the A-Arm to bend before damaging the bulkhead. What is the goldilocks A-Arm for this? Not too strong but not too weak?
Stock with the Arm Candy braces. The braces strengthen the thinnest inner most area of the A-Arms that can fail from just catching a rock with the ski skags. If you still hit something hard the braced arm, it will fail outside the brace. We have not had any reports of bulkheads failing with braces. Failures without the braces also move the arm in enough that shock damage easily occurs. When hitting an object with the braces on, the bend is farther out on the arm so the shock has never been damaged in any of the incidence we have heard about.
 

law.74

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Reviving an old thread while researching new arms for a new to me Axys.

A few observations about T-rex arms and rod ends.

I ran T-rex fab arms for two seasons. Intermediate skill level so I still hit stuff especially in low snow conditions. Last season I broke one rod end on a very hard impact. The season prior I broke 3 or 4. I upgraded from the no-name rod ends that come with the arms to FK rod ends (mid grade). I have not broken any of the upgraded rod ends but I am hitting stuff less. Last season's snow depth certainly helped. Ditching carbides for smooth wear bars might also have helped.

I carried spare rod ends having purchased the kit to have the built in "fuse". Unfortunately as someone else mentioned its not just the rod end that can break or bend. The upper arm bushings can deform and the bolt bend. One time I could not reuse the upper misalignment bushings or the bolt as they were stuck in the broken rod end. I now carry a full set of bushings, rod ends and bolts. Not an insignificant amount of weight. Insurance I suppose...

My very first rod end failure was hitting a rock below the snow surface. An impact that would not have resulted in failure of OEM arms based on prior experience. A bit disappointing for sure. Thus I cannot recommend the rod ends that come with Trex arms. Upgrading rod ends costs $110 plus shipping not including spares. Add $55+ for one each spare. Add $10 per set of bushings from Trex. It adds up making T-rex arms less of a value option (unless they include better rod ends).
I'd rather not put a weak rod end in just to have to change it later. Hopefully the mid grade rod ends still act as a fuse.

I reached out to Trex two seasons ago and asked about the grade of rod end used. No response.
Have they changed rod ends after initial feedback? I'll reach out again and see what they have to say.
 

Scott

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I went through 3 or 4 arms on my left side.
Decided to go with Ice Age this spring. REALLY happy with them so far.
They have extra clearance and they do look sharp, but not subtle.
 

law.74

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I reached out to Trex two seasons ago and asked about the grade of rod end used. No response.
Have they changed rod ends after initial feedback? I'll reach out again and see what they have to say.
I got a response this time. No change in rod ends sold currently vs when I purchased in 2021.

Rod ends are rated by a number of variables but the one listed when buying online is static load capacity.

T-rex uses 10k 1/2” rod ends and 11k 5/8” rod ends. They will not sell the kit without them.
Midgrade alloy steel FK rod ends that I run cost similarly to what T-rex sells theirs for, but are rated at 16k and 18k respectively.

I don’t know if I am jeopardizing arm failure by running these stronger joints. I broke the included upper joints on minor impacts that would not have bent an OEM arm (in my experience).

Now I am curious what rod end Alternative impact and Skinz include with their kits.

may your land mines be burried under many feet of snow
 
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