Was plowing 12" of snow today and thought I'd use 4L. Truck did fine with factory tires and no weight in back. But the shifts of transmission were much 'stronger'. Had to have transmission in N before engagement like all the others but was concerned about the harsh shifts....anyone else have this happen?

 

I've always been prompted to put in N to get in 4L... my truck also seems to shift abruptly. I have only used 4L a few times and I've wondered if the trans needs some learning time. I thought I broke something the first time it shifted when I was playing around trying it out lol. I also noticed that once I got in 4L sport mode would turn off.

 

If I'm not mistaken(I'm no expert)...but I think the torque converter is locked all the time in 4L so it's basically a direct drive causing the harsher shifts. I could be wrong and I'm sure somebody else will pipe in.

 

Abrupt shifts are pretty much what I've always experienced in 4L with automatic transmissions. Normally, when I need 4L, I am running slow and steady and don't experience many shifts.

 

Yes, granted but plowing you get a lot of forward to reverse shifts... They are hard!

 

Why wouldn’t 4hi be suitable for plowing?

 

Harder shifts are what I experience as well, and in a lot of cases they don't happen until higher than 'normal' RPMs. For me it's on sand though.

The transmission whine is much louder too. Does any one know why? Possibly 'straight cut' gears?

 

I don't plow, but I believe what you're saying.

 

I experience the same very harsh shifts at high RPM's. It hold the gears a lot longer and then shifts hard. It's never been a problem for me as I tow a trailer through some soft sandy trails and try to hold a constant speed anyway to carry enough momentum to not dig in. I always thought this was just how the computer was programed to control the transmission while in 4 low.

 

Agree with big cat.. why 4L for plowing.. you should be just fine in 4H.. drop your shifter down into 1 or 2