My husqavarna 46 zero turn lawn mower has a steering problem.

I suspect that you lost a belt, or it was slipping badly. If the water pump was not turning it would get hot and you could lose your fluid, the steering pump wouldn't be turning either. Either pump could have leaked onto the belt, making it slip too.

Bad seat switch possibly. Did you try to jump start it?

Why Is My Automatic Transmission Slipping? If you have an automatic transmission and it "slips" while you are driving it-that is, the car engine revs without the power going to the wheels-the most common cause (though not the only possible cause) is low transmission fluid. If the slipping is caused by low fluid, it will get worse as the transmission gets hotter.
Why Is My Manual Transmission Slipping? A standard ("manual") transmission uses fluid too, but leaks aren't a common issue; a standard transmission could lose all its fluid and never slip at all, though eventually it would lock up while driving down the road. If you have a standard transmission, and it's slipping-the engine revs but it doesn't transmit power to the wheels-the problem is usually in the clutch.
Further down in the article I discuss how to diagnose this problem.
Sounds Like Low Transmission Fluid to Me

Trans is shot. They cost around $600 to 1000 new. You can probably find one used for a couple hundred dollars. There are no rebuild kits for them. (Assuming this is not a zero turn) zero turns you can easily double the price....for each of the two drive units

Can you post a picture of the part you are trying to remove? Do you have a gear puller? It may be pressed on.

is their any chance the belt is getting wet and slipping or do you lose power steering whenever you turn? if so check that all your power steering lines are not leaking (presure line will spray out , return line will just drip) check and repair as necesary

I have had the almost same problem twice. A 'thump', like the engine missed a fire and tach drops. Seems OK after restart. Electrical? Timing chain slip?
Has 135,000 mile. Any clues?

Check your tranny fluid levels- if they are low your transmition will slip between gears, however if you notice any kind of free reving while its shifting (like being reved up when in park or neutral) then the hydrostatic clutches are slipping and the transmition needs repair.

Another thing you should investigate is your transmition kick down bar (it shifts the trany into a lower gear when accelerating hard to help pick up speed.

a 2008 toureg? Is this not still covered by warranty? 2 years unlimited milage, 3 years up to 60,000 miles.

This sounds to me like it may actually be your steering gearbox, Chevrolet is known for having gearbox issues. Sounds like there may be a dead spot in the gearbox, but it is only noticeable at higher speeds and not slower speeds. Would recommend having it looked at. Usually a suspension issue wouldn't cause that type of feeling. Hope this helps.