My wife and I have been washing our wooden handled steak knives by hand for years, because we “knew” that the dishwasher would ruin them. Then tonight she asked me how I knew this and I brilliantly replied “I dunno.”
So, anybody know anything about this?
The constant wetting and drying in a dishwasher will ruin the handle and cause cracks in the wood. Additionally, the motion of the knife against other things in the washer could cause nicks in the blade.
Two good reasons to wash them by hand.
Your steak knives will end up looking and feeling like your deck.
In general, it’s a bad idea to put sharp knives in the dishwasher. Through a number of factors, the blade will end up getting dull after several washes. My family’s knives are a lost cause, so into the dishwasher they go.
-Lil
Dishwashers have rather intense mechanical action from their high pressure water jets, and dishwasher detergent is fairly harsh. Not good for wood.
That aside, an occasional wiping of the handles with mineral oil will help preserve them.
I had some wonderful wooden spoons that we dropped in the dishwasher soon after getting them.
After the wash cycle, the wood has a completely different texture; they’re not wonderful anymore.
You can put anything you want to into a dishwasher, as long as it will fit. 
That said, I would advise against washing anything made of wood (knife handles, cutting boards, wooden utensils, etc.) in a dishwasher, for all of the reasons given above.
This is experience talking, BTW. My mother regularly put all of her flatware and utensils in the dishwasher so that she wouldn’t have to wash them, regardless of their materials. The handles of the “good” steak knives were usually warped, cracked, and/or faded as a result. Wooden spoons rarely made it through a year before breaking. Cutting boards were too warped to use.
The lesson she learned, though, was NOT “Don’t put wood in the dishwasher,” but “Don’t use anything made of wood in the kitchen because it will warp or crack within a few months.”
In my own kitchen, I have a set of wooden cooking utensils, wooden-handled knives (both steak and chef), and my favorite wooden cutting board. And I’ve had some of them for more than a decade with no usability problems. Everything wooden is washed by hand.
well as far as I know. I am pretty confident that it won’t hurt the dishwasher. It might not even hurt the knife. It probably will ruin it, but it might not. Depends on how the handle has been treated.
IMHO, it would not be a smart thing to do, but it could be done.
Mr. Neville, who is our household expert on what can and can’t go through the dishwasher, says they can’t.
That’s the lesson I take from it- “Don’t buy anything that can’t go in the dishwasher unless there really isn’t an alternative” (good chef’s knives would be an example where there isn’t an alternative).
Well, if the wood is at all porous I would not put them in a dishwasher.
If the knives are expensive, I would not put them in a dishwasher.
On the other hand, if the knives are cheap, non porous and you are lazy (like me) then putting them in the dishwasher would at worst lead to buying replacements a year or so’s time.
In addition to what others have pointed out, the wooden handles will tend to swell a bit when wet and then shrink back to their previous size when dry, loosening the rivets that hold the handle to the blade.
Interestingly enough, I have a nice set of Henkel knives that say they’re dishwasher safe as long as each knife gets its own compartment in the silverware bin, thus protecting them from chipping by other implements.
We’ve been putting the same wooden-handled steak knives in the dishwasher for 12 years. They look a bit older, naturally, but otherwise are fine. My motto is, everything goes into the dishwasher. If I have to buy another set of 6 steak knives in, oh, another 5 years, I can live with that.
Wow, I totally read that last vowel wrong. :o
Thank you for being my voice of reason, because I have no intention of not continuing to put my el cheapo but fine working wooden handled steak knives in the dishwasher 
Thanks