I am not sure about that. I do know that forced downshifts in the regular gears are hard on everything unless the speed matches the RPM when the lower gear clutches engage. Putting the lever in 2 or 1 generally causes a noticable deceleration, and that energy is being absorbed by the clutches and other transmission internal parts.

The general point is that if the shift seems rough, it probably is not good for the transmission. Normal upshifts can be firm (but not harsh) without doing damage, and as all the shift kit purveyors point out, too soft a shift means that the clutches are slipping and wearing out.

If your tranny shifts smoothly between OD and high, I doubt that you are doing any harm. That ratio "step" is probably smaller than dropping from 3rd to 2nd, or to 1st.

 

ok, that is what i thought

 

A really bad thing to do to an automatic transmisson is to shift between forward and reverse while still rolling in the opposite directon. Heavy equipment (loaders, dozers, etc.) are designed assuming that the operator will do this, but an operator who stops before changing directons will make a powershift transmission last four times longer!

 

I used to love doing that with this articulated steer, rough terrain forklift I drive in the Army. Full speed forward and slam it in reverse. I could ride a pretty nice rear wheelie if the lift was up. Like this...YouTube - loader wheelie part1

 

That's not a correct statement, I just changed a broken diode in my son's 2001 F350, 4X4, V10 at 136,000 miles, and I had one in my 2001 F350, 2WD, V10, lasted 108,000 miles.. Both original transmissions, at the factory you get what they have.

 

Mark Kovalsky has said numerous times it was only the diesels that had the bad diode, but ... I distinctly remember it wasn't diesel-specific. Dunno... I'm waiting for mine to go

 

1; No warning. Once it doesn't funtion correctly it needs to come out, or occasionally they can't be repaired from the pan. It's better to respond as soon as it acts up or the price of repair can double and triple. Especially if it slips because this causes heat, contaminates the oil, and will quickly escalate. Some shift patterns can be remedied externally.

2; You can't tell unless a rebuider left a name or tag on it, or if you routinely rebuild them you can sometimes tell by the changed internal parts. Sometimes bolts are left out (or loose) of the re-install also. A rebuilder can usually tell if someone has been in there.

3; Nothing you can do other than change oil. It's still debatable whether trans additives that soften seals and O-rings work well or cause more problems. Usually by the time you think they might help it is too late.

4; That's up to you. I don't like sticks because why shift when you don't need to.

 

i disagree with 4. the way I feel is "why let it shift for you when you could be shifting?"

 

I guess you could always run around the truck 3 times before you get in also. You could get some extra exersize that way too.

 

243,000 and still going. Changed the trans filter and the oil that drained out every 30K miles and never shifted from D to R/ R to D while vehicle was rolling.

 

Like Art said, no gasers were sold with the Diode, they changed them all out before they started selling the trucks. From what I read from Mark. I also wonder about your and your son having the Diode in his trans.

 

1 What warning do you get before it dies?

Not much of one, parents were driving my truck a few days before it died. It shifted rough and something else they mentioned, but they thought it was just a fluke. (kinda wish it were) When it finally went on me, it wouldn't shift out of second gear until I let off the gas and stepped on it again. The truck was drivable, but wasn't sure how long it would be.

2 How do i tell if my trans was ever replaced?

If it was done by Ford, there's usually a tag on the driver side of the transmission. Other shops may leave their mark the same way in one form or another.

3 What can i do to prolong its life 145,000 miles currently?

Flush every 30K, use the most current fluid required by Ford, and upgrade your existing trans cooler to a 6.0 trans cooler. It worked wonders for my truck and is the best way to keep your 4R100 cool under most conditions.

You should also look into a shift-kit to firm up your shifts and make things more efficient. (keeps your trans cooler too)

I did both on my truck and my Ford reman tranny made it well past 100K with little to no problems. The only thing it needed was a reflash for the delayed shift into overdrive.

4 when it dies rebuild or swap in a standard?

Rebuild. The 4R100 is great transmission, it's only weak points is the torque convertor and the trans cooler. Yeah sure, under normal conditions the stock stuff cuts it, but after awhile it's time to upgrade. If your trans goes, it's a blessing in disguise because if you go with a BTS trans or a John Wood tranny, it's vitually indestructable and you'll never have to buy one again.

 

does the 6.0 have bigger cooler than a 6.8 or 7.3?

 

Don't know about the 6.8, but the 6.0L cooler is bigger than the 7.3L. I've heard of these trannies breaking anywhere from 38K to well over 200K.

 

stopped by the shop today,they just pulled it out.he will take apart tomorrow to see.the truck is used for work as delivery truck,i have had up to 12,000 lbs on the deck but most times around7000 max.changed the fluid every 3 mths.he said they put all updated parts in,valvebody,torq,clutches and springs.i forgot to ask about shift points,mine allways shifted out of low to soon