Transmissions and tuners?
 

I recently had my transmission serviced at a place that I've been going to for years, so I trust their opinion. I asked them if I put a tuner on my ' 08 KR with 160k will it hurt anything? Because I've read of hard shifts after the tuner install, they told to absolutely stay away from tuners unless I want to rebuild my tranny. I really wanted to get a tuner and bring that 5.4 to life but I don't want to grenade my tranny in the process.
Thanks for any input

The tuner does not create hard shifts.
There are user adjustable parameters that can be set to create hard shifts. This would be done by the user not knowing what they are doing. If an adjustment is made, test the results - adjust again if not correct.
There are many threads posted on this forum where posters personal tune parameters are documented.
I have an Edge Evo in my 2004. The shifts are firm and positive - not hard.

Get a tuner. The results will make your truck seem like a different vehicle. Better response, more power, crisper shifts. More pluses are error code reading, many parameters such as temperatures and pressures available to display.

I have been running MPT custom tunes for 50,000 miles. My tranny shifts are firm with no issues. Checked the fluid this past weekend and its like new.

The bolded statement is incorrect as all tuners increase shift firmness as power is increased.

As for your trusted shop, I am surprised they are being so cautious.

For clarity, anytime you increase power you are putting more stain on all components, including the transmission.

HOWEVER, firm shift themselves are not a problem and are, in fact, a good thing. OEM set up the trans to shift soft because it makes for a good driving experience. They do this by slowing down the shift between gears, meaning more slippage, and heat, as the shift occurs.

Tuners speed up the shift and remove some of the slippage. In reality this is a good thing for your transmission as it reduces slippage, internal wear and heat build up.

The tow/haul mode on a truck is doing the same thing as a tuner (for the transmission part) but on a more regular basis. If it was bad for your transmission do you think that the OEMs would put a button in the truck to do the same thing?

This is, of course, a very simplified version of what is going on but I think this gives you a basic explanation that you can start to formulate a decision on.

FWIW, I prefer a tuner to stock, especially for towing and hauling. I generally leave my tuner on level 2 or the towing mode. I do not want to need to run high octane fuel and like the better shift pattern of the towing mode.

Thanks for all the info, I definitely need to research them some more

I had my 01 5.4 2v Superduty tuned for 180,000 miles. No engine or transmission issues at all. Only part to "fail" on the truck was the starter. My 07 5.4 3v has 155K on it now and 40K of that has been tuned, no issues at all. As Dirttracker18 stated, firmer shifts is actually the transmission clutches shifting quicker, with less prolonged friction. Tunes that "firm up" the shift points are actually known or reportedly known to make your transmission work easier. Having 2 vehicles with combined tuning of over 200K and zero transmission problems, I believe that tuners dont hurt transmissions unless you make your settings the absolute highest possible and drive like a 16 year old everywhere.