Husqvarna LGT48DXL K46 Transmission

wesf

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I recently looked at and purchased a used Husqvarna LGT48DXL, according to what I find online it has a Tuff Torq K46 transmission. By all indications it is right at 4 years old, supposedly used on a 3/4 to 1 acre lot for those years. The hour meter is damaged from some outdoor storage, so I have no idea of the true hours. When test driving, it seemed to drift forward pretty easily on a moderate hill (not the same property where it was originally used - supposedly that was pretty flat) in neutral, but I didn't think too much about it. Didn't seem to be slipping or having any issues accelerating or going up a hill. I agreed to purchase it, paid cash, and came back that evening to pick it up and it didn't want to start, guessing the battery is about shot. Anyway, had to push it up on the trailer, and I realized that I could easily push it without pulling out the lever in the back to "disengage" the transmission. My other/old mower is a 2001 model Craftsman LT1000 with hydrostatic drive as well, and I have to do that to push it while not running. I spent the night worrying that I'd just bought a lemon and contacted the person I bought it from to see if they might be willing to take it back...I won't bore you with the whole situation, but still waiting to find out on that. Got the battery charged enough to start it last evening and messed around with it in the yard, and it still seems to be a strong transmission, easily going straight up the few moderately steep parts of my yard that I normally mow across, but I can still push it with the engine stopped and the transmission release lever firmly in the inward position. It seems to drift a bit more on a downhill while "in gear" before catching than my old one, but it also didn't just totally run away either.

I'm just beginning to wonder now if I am too overly worried and it is fine and nothing to worry about. I would appreciate any thoughts anyone has on this. Is it ok, or should I run away from it (if I even get that option)? I got it at a decent price, so I think I still wouldn't be hurt too bad if I had to do a repair/replacement on it, but would still be aggravating...

Thanks!

Wesley
 

bertsmobile1

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Yes the transmission is on the way out
Change the oil, go one grade thicker.
I test trannys when unloading from my tilt trailer
If I push them and they resist moving and stop the instant I stop pushing they are in tip top condition
If they push with slight resistance & stop when I stop pushing, they are wearing
If they roll easily and keep going then I can usually get another few seasons out of them with fresh heavier oil
If the take off like a rabbit all by themselves when the brake is released then it is off to the tranny man for repairs
Standard oil is 20W50 so I use 40W60 and tell the customer to warm the ranny up for 5 minutes before moving off .
The bits that wear are the pump & motor which is a drop in replacement part so you will not do any irreversable damage if you run it till it is dead .
 

Rivets

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I’m guessing that the unit might be older than 4 years. How does the drive belt and all tension pulleys look? May just need a new belt, if it has not been changed in the last few years. No start may be a red flag, but we need to have more info. Please look under the seat and post the model and serial numbers for your unit. With them we can come closer to the exact date of manufacture. Better yet, post pictures of the units and engine ID numbers. May have to resize the pictures to attach them.
 

wesf

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Thank you for the fast replies. I was afraid that might be the case. Sounds like the best bet is to give it back if they will take it, but I'm not going to hold out too much hope there. Also sounds like maybe my old Craftsman is still doing ok! Only serious thing wrong with it is a hole in the deck where one of the forward mounted stabilizer bars rusted loose. Probably not worth the cost of a deck, if I could even still get a new one.

I understand the transmission (or is transaxle the right word?) is a sealed unit - how would I go about changing the oil? You mention the pump & motor being a drop in replacement - is there much more to a repair/overhaul than replacing that part? Is it a difficult repair? I've never done any such work, but game to try most anything if a decent guide is available somewhere.

The mower definitely looks older than 4 years, but was stored outside, supposedly under a tarp, though I'm not convinced of the latter part, at least not all year round. There's a wire under the seat with a tag that says something about revision '18. The battery is dated May '19. I can't easily get to it in the rain today, but as I understand it the first 6 digits of the s/n are MMDDYY format, I recall it being built Nov 18 or something like that.

I have not looked at the drive belt, but as well as it powers up a hill, I wouldn't think that would be a problem, at least not to roll as easily as it does when stopped. When I went to look at it, the guy hit the key and it jerked and stopped, presumably not quite enough juice to overcome the compression of the engine. Hit it again and it fired right up. When I picked it up, it wouldn't get past the jerk to a stop. After a while on the charger, it would crank, though seemed a bit weak and wouldn't fire. Tried again after a bit and gave it a little choke and it fired right up, though ran rough. After running for a brief time, I messed with the choke again and it settled down, I suspect I hadn't quite pushed the choke in all the way. Will have to try it again when the weather clears to be sure. It's a Kohler twin cylinder, supposedly 25hp I think.
 

bertsmobile1

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Go to the tranny makers web site and download the repair manual then access it against your mechanical skills.
The repair is not difficult , simply undo the 2 halves pull out th e old & drop in the new .
many just push into place .
Down side is the unit must be clean, really clean.
I blow down, degrease , pressure wash , soday blast & pressure wash again
Then when you pull them apart ther will be a lot of silicon to be removed with petrol soaked rags
When not being worked on the units must be covered with a damp cloth ( old sheets work well )
Photos are essential because the swash plate ( the bit that controls the speed & direction ) fits both ways depending upon the actual spec so your controls can end up being backwards .
A really dead tranny will scream at you when you depress the pedals, a worn ne will groan and a really good one will be quiet .
It is prudent to also replace the axel seals while it is apart .

To change the oil remove the tranny , clean around the fillport on the top remove the fill port and tip it upside down.
This will take a long time so use some sort of support to hold it there
Return the unit to the upright position then fill with the prescribed amount of oil ( some of them take a lot of oil )
Now you can use a power drill to spind the drive pulley while you purge the air out or you can put it back in the mower & purge
Some time the purge will take 5 minutes & some times it will take all day

come back latter on if you want full instruction.

Not as difficult as it sounds but you need to be careful and of course CLEAN
I used to do mine in the workshop shower after wetting the walls & floor but I am on a flood plane with loads of very fine dust
 

wesf

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Thanks so much for that information. Reading what you typed and watching some doing a repair on one on YouTube, it doesn't look too difficult. My main concern is just being able to get it done correctly without someone knowledgeable looking over my shoulder to correct anything a first timer might goof up. Also not sure I would have an appropriate place to do such an overhaul, don't have a shop, and sounds like something that maybe shouldn't be done in the back yard under the shade tree.

The oil change sounds like not too big of a deal, aside from the headache of having to remove the unit from the mower.

Wishing I'd not made the decision to buy this thing! Oh well, live and learn I guess...

Thanks again,

Wesley
 

bertsmobile1

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Start with an oil change to heavier oil
Then if it works for a couple of seasons you have the time to research the repair.
IT is not difficult
All parts drop in .
Some have C or E clips but most will not need a spannar ( wrench to some ) after the cases are split
If you have specific questions ask
Take photos ( will need to be resized to load directly to the forum ) and download the parts diagram
You will get better advice if you use the correct part names ( as per parts books ) because we will all know exactly what you are talking about
The only rela trick is putting the Swash Plate in the right way round
Even if wrong, all that will happen is the pedal directions will be reversed
It is like this beaise some control rods pull for forward while others push for forward
 
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