Toy truck axles are about 1 1/2 -2" narrower on each side so about 3-4" narrower overall. This would require wheel spacers to get the same width..
So you could do it I suppose.
We went with FJ80 axles for that reason. We didn't want to go narrower. FJ80 axles are about 3" wider on each side, so about 6" wider overall than a sidekick axle.
Your sammy axle will require wheel spacers to get it to the same width as a sidekick, or you'll need to extend one side and get a custom axle shaft.
I can understand the importance of wanting to stay Suzuki though!.

We did for the longest time.
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