Honda Trx300 final drive (rear diff)

[Paul Hannan]

Hey, 

Looking for some advice regarding rear diff issue.

I have lost all drive power to the rear wheels from the diff. I have drained the diff oil and have not really found anything to scary apart from the colour of the oil....  Ive jacked the bike up.  Then I took the side cover off the transfer case to confirm drive shaft is all ok. And spins when put in gear etc. Then check the rear diff oil filler where you can see the crown wheel (final gear) that was spinning all ok.

My guess the spline how stripped on something either final drive or the main axle. Main question is how do I tell if the final drive splines are stripped?

Also during the process I managed to bugger the diff oil filler bolt plug thingee! Any ideas where I can get one? I’m in New Zealand if that helps.

cheers

 

[Ajmboy]

I think you would visibly see if there was gear damage. Are there any metal shavings in the oil? Check out this topic:

Have you done a spline inspection? Check out this video:

 

[Paul Hannan]

No drain the oil no steel seen. Made a start yesterday pull the shaft out. Hopefully by the weekend I will know more. I’ve tracked down a second hand one. Hopefully that all that is buggered. Any idea on how to flash all the old oil out of the diff. I’m not really wanting to strip it down? Cheers

[BRoth82]

I had the splines go out on my 450S, I ended up replacing the main drive shaft and the main drive gear.  I could tell it was out by jacking up the back end then putting it in 1st gear and rotating the rear tires, I could spin them with out too much effort.  It wasn't too bad of a repair job. 

[KJINTF]

Did you find the cause?

I have the same machine and was wondering what went wrong?

[BRoth82]

I know on mine it was from pulling things that were way to heavy for it.  It was a farm ATV for a long time before I got it.

[colin james]

What year is the trx 300

[KJINTF]

Mine is a 1999 TRX300 and I have been using it to pull a trailer loaded with firewood for the past 15 years 

[Cjames58]

did you check the drive shaft connection to the rear diff

[Paul Hannan]

Sorry for the delay. It’s all fixed now. I purchased a second hand main shaft and replaced it my self. Easy job  apart from the seized castlated nut on the left hand side. Ended up having to grind it off! 

Flashed diff oil several times. All good.

Bikes for sell now since been replaced with Honda foreman 500!