max 4 won't move?

[bigmuddy]

Looking for help with my max 4. This is my first 6x6 so I'm a little green to this world but I can relate most parts to other things I've worked on. I bought what I thought was a pretty clean max 4 roughly a 96. I took it out for the first time and found myself stuck in Swamp 300 yards from any kind of solid ground with something froze up in the tranny I'm assuming. I know it rolls freely so I don't think it's anything with the chains but before it froze up I heard a squealing w hg en I gave it enough gas to engage the clutches. It seems to be in the t-20. But I'm open to suggestions by people more experienced than me with these machines. I also managed to break both rear axle shear pins. Any idea what I did? Thanks in advance.

[ARGOJIM]

Replace the bolts and you may be ok.

[bigmuddy]

The front 4 tires won't turn either, and when I give it gas it burns the belt when it's in forward or reverse. In neutral it will spin the clutches but is working the engine.

[ARGOJIM]

I would start with the bolts first, then check the belt deflection which I believe is 1-1/2 inch deflection, then measure the top width of the belt should be 1-3/16. My Max 2 and Buffalo tuck drive off the center axles, I believe Max IV's drive off the rear axles, so if you have no rear drive you have no drive.

[ARGOJIM]

Also check the parking brake is not on. Hopefully you do not have a trans band issue, if your squealing is not the belt you may.

[bigmuddy]

It is driven off the rear axles, but the engine bogging down makes me believe it's something bigger. When the squealing started it even felt like there was a ton of resistance. Probably should have shut it down but when I'm stuck a wire crosses and I have to get out. Must be from my mudding days with trucks when I was younger.

[PlumCrazy]

You broke both rear axle/sprocket bolts? Wow!
Unless someone has modified the bolts by turning a relief/brake point into them, they are not shear pins.
If the rear axle bolts are broke, the Max T20 will still mechanically power the other four axles, just not drive the rear axles, if your sprockets are a welded two sprocket one-piece setup like mine.
The rear sprockets can walk out of alignment without a bolt retaining them though.
Removing the bolts from the front axle and putting them in the rear and then removing the front chains, should get you home if nothing else is boundup/broken.
Are all the axle bearing concentric collars still in place so the axles can not move in&out?
Are the clutches moving correctly when rpm is increased?
Does reverse still work?
How tight are the chains?
My Max doesn't want to move at all with REALLY tight chains, and the increased load makes a big rubbing vibration.

[bigmuddy]

All the collars are still in place. I did replace the rear axle bolts after I bought it, I didn't notice it when I test drove it. But they broke again so i think i have a wore axle bolt hole problem,The clutches seem to be working ok. I'm leaning toward a bad t-20 bearing, but I don't have time to tear it apart right now. I was hoping for a simple fix, but it's not looking to good.

[PlumCrazy]

All the collars are still in place. I did replace the rear axle bolts after I bought it, I didn't notice it when I test drove it. But they broke again so i think i have a wore axle bolt hole problem,The clutches seem to be working ok. I'm leaning toward a bad t-20 bearing, but I don't have time to tear it apart right now. I was hoping for a simple fix, but it's not looking to good.

So you broke 4 axles bolts on the rear.
A 7/16" grade 2 bolt has a shear of something like 5000#
What bolts did you buy, where did you buy them, did you save the original ones?
.
Where are you located at?

[amphibious drew]

Breaking bolts is common if you use too short of bolt. If any thread is in the sprocket or axle tube, it will break. I use grade 8 bolts and buy them longer than needed to ensure the unthreaded part is the only part in the assembly. Then I just chop off to length once installed.