John Deere X300R - which transmission?

stagestruck · Mar 30, 2021

I recently picked up a used X300R lawn tractor, the one with the rear bagger. All was going well until I saw big globs of oil on the driveway where the tractor had driven. Felt around a bit and found the oil was coming from the transmission area. Googled X300R transmission and the wisdom of the internet say that this model tractor has a tufftorq k46 transmission and there are all sorts of issues reported with them. Sinking feeling... Anyway I took off the rear bagger and the first thing I see is that the transmission has an oil reservoir hooked up to it. But surely the k46’s are sealed units, they don’t have a separate reservoir?! The oil leak was caused by the reservoir separating from the hose - easy fix, reattach the reservoir with a jubilee clip and refill with oil. But now I’m curious, so I find the transmission part number, 7A545084141 but the Tufftorq parts site can’t find that part number. However there is a JD part number: AM134519, but googling that says that the p/n is now MIA12566. Entering that into the tufftorq parts site says that it’s a K57Z.

I’m now confused - does my tractor have a K57 transmission? It would seem so. was that an option when new, the tractor is a 2009 Model. But even if it’s a k46 or k57 what about this external oil reservoir? Nothing I can find would indicate that either of these transmissions have one. Not that it really matters, again, I can just reattach the reservoir and refill with oil and hopefully everything will be fine, but it’s curious. Lastly, if it is a k57 transmission, can I just get one of those surplus k57 units from surpluscenter.com and not have to worry about all the retrofitting that the “k57 upgrade thread“ elsewhere on this forum described? Or do these transmissions vary in specs even with the same model number? Beginning to think they do...

oldnslo · Mar 30, 2021

Tufftorq may put a JD OEM specific part number on models for Deere that will not show up as standard item on their website. My limited understanding is the X3** series where K46 but I would not bet my life savings on that.

Gem99ultra · Mar 31, 2021

Not answering your need/want to know... but I have a 2001 Husqvarna R155 Rider with the K46 transmission. It does have the external oil reservoir and it does leak. Perhaps not a bad as your is leaking, but it does have to be refilled about once a month.

The R155 had been through he** with something well over 2500 hours on it. I've been refilling it with simple motor oil for the last 15 years. Bet that hasn't been 'good' for it

Nonetheless, that old mower has been loyal, never failing to provide the finest lawn cut of any mowers that I've had. And still going strong.

No matter whether it's a K46 or K57... My advice is to try to slow your oil leak down to an acceptable level, and run it until it dies. Of course, you now owe me 2-cents.