I have a 2005 F350 SRW 6.0L deisel. Occassionally when towing in the tow haul mode the trans will downshift violently when slowing down in the 15-20 mph range. The first time I felt it, I thought I was rear-ended. The dealer told me it was a "characteristic" of this transmission. Has anyone experienced this?

 

I have experienced this in my 04 F250 6.0 when using the Tow/Haul, I thought it was normal, having a firm hard shift when hauling heavy loads, one of the reasons for having the tow/haul and not the smooth shift when in the normal operating mode.

 

It is supposed to do that. Especially on downhills when you are accelerating without applying throttle. My 06 F250 does it and my 02 Chevy 1 ton did it too. When in the tow/haul mode of course. Should not do it if it is not in tow/haul.

 

Does the hard downshift (or harder downshifts) happen when you apply the brakes? If so, the transmission is working like it should.

When hooked up to a trailer those downshifts make towing much easier and save your truck's brakes.

Lou Braun

 

Yeah, working how it should. I LOVE Tow/Haul mode. It works great.

-Matt

 

The orginal PCM program allowed this downshifting action in ALL gears when slowing down. Ford received too many complaints and reflashed the PCMs to have the 2-1 downshift be the firmmer downshift when in TH mode.

 

My 2006 F350 has an extrememly hard 3-2 downshift at times. It happens in T/H mode when there is no load on the truck. I pull a 30 foot fifth wheel that weighs about 11,800 pounds loaded and the first time the truck did the hard downshift was towing it. The dealer reflashed the PCM and it no longer does it while towing b;ut will do it when not towing.
The tech at the dealer said a "clunk" when downshifting is normal however my truck experiences a very hard jolt, so hard it causes my wife to catch her breath when she feels it. I don't think it should hit that hard and intend to have the dealer try again to correct it, this will be the third time. The 2004 F350 I had before this one did not have this problem. It had the same engine and transmission.

 

My 2005 250 did the same thing and took it to the dealer and they fixed it. Not sure what they did but it works fine now. Mine was so bad that thought the engine was locking up when it down shifted.

 

rshaddy10, If it's a problem then why are you driving around in t/h mode w/o a load. Doesn't sound like there's anything for the dealer to fix.

 

They did something to it and now it works fine. I only use it when I tow heavy boats.