RACarvalho

It may be that the transmission harshness is already affecting the engine.....

Apples

Respectfully, how is that possible. Unless the transmission software suddenly triggers reverse gear while going forward, transmission "harshness" (please describe your version so we may better understand), transmission shift harshness, or, shift firmness, will not harm an engine. Shift firmness will actually prolong the life of the transmission internal clutch packs (but appear to be detrimental to some folks' opinion of drivability comfort).

idrive

iTrader: (3)

Guess I'm just wondering if this is the Joseph LaCava, as in Tiger's Caddy?

jsnell321

Been following this thread for a while as I am experiencing all of these symptoms. I was dealing with the chatter on decel until my check engine light came on one morning on the way to work. Ford pass told me it was misfire and I took my truck in that morning. My dealer replaced my VCT Phaser for the chatter and apparently they thought that would fix the misfire, as that is the only thing they did to my truck. May work on some, but the replacement of the VCT Phaser did not fix the decel chatter issue. Will update once I get my truck back from the dealer the second time.

RACarvalho

Harshness:
When you are coming to a stop and it shifts from 4th to 3rd gear so out of revs that the people inside the truck think you slam the brakes OR
when accelerating, it changes from the 5th gear to the 6th gear so violently that it seems the torque converter was closed.....

Some days these two happened to me more than 5 times in a stretch of city drive of less than 10 miles (stop signs) and yet, no fault code and the dealer says it's "normal".
The truck is heavy so what the drive train "feels" is way worst than what we feel inside the truck.
Everything is stressed in the drive train during those events and if you continue to drive under that condition, one day you will get the right angle/right timing where the valve train will have problems absorbing the counter torque stress.
Also the engine mounts and several other links on the drive line will fail prematurely.....
My previous vehicle was a 2006 model with a GM 5 speed transmission with 100K+ miles and until today I can't fell the shifts and only know it shifted because the change on engine revs... This previous vehicle towed a camper at the towing limit for 12K miles in reaching 11000ft in Denver and 105F in Nevada and the transmission is still smooth like silk.
THAT is a properly operating transmission.
FYI: last Thursday I erased the adaptation and the truck shifting changed completely. Since then I drove 200 miles and it is shifting right all the gears. So this is not a mechanical problem but a software problem. Since the dealer said it's "normal", I bought a battery disconnect switch and will be erasing the adaptation as soon as I notice any harshness on shifting.

plncrzy

I now have 16000km (9600 mi) on my 5.0 supercrew with tow package and 3.55 diff.

Issues I encountered since the rattle started;

1. Unusual gear changing (at low speeds truck stays in gear too long then changes suddenly making truck "lurch forward".
2. Shuddering or slippage from transmission at low speed acceleration..
3. when towing a 5000 pound camper in towing mode, on deceleration (for a curve) the transmission automatically downshifted to the point where the engine red-lined for several seconds.
4. Transmission stays in 7'th or 8'th gear on highway at 90km/h (50mph).
5. Rattle from truck got louder as the mileage went on the truck from almost new.
6. Occasional very rough idle at start up.
7. Occasional clunk or bang as starter disengages at start up.


I recently took it to the dealer with these issues and they did the following;

1. re-programed the pcm.
2. ordered a transmission valve body to be replaced when they receive it.


For the first 200 km (120 mi) after the re-programing.. the rattle was non-existent. then very slowly I began hearing it again.

When the dealer calls me in for valvle body replacement, I will mention again the rattle has returned.


At this point I am not sure if the rattle comes from the transmission or an engine component?

I am anxious to get this resolved however. This is the first truck I purchased from Ford since my 1990 Ranger 4.0... after that truck I swore that I would never buy ford again... now I am starting to think that I should have kept that promise.

w00t692

You don't want your transmission in 8th gear at 50 mph? That's perfect RPM wise. if it was in 9th it would be well under 1500 rpms and be dead to pedal input without a downshift generally.

OCMike

iTrader: (1)

I realize that Ford says you can run regular 87(RON) in 2018 5.0 but old hot-rodder in me says you should never run that low grade of fuel in an engine with 12:1 compression ratio. I'm curious when you towing do you run a higher grade of fuel?

In my '18 5.0 I've only ran E85 prior to the Whipple, then 92 after. I haven't notice any of these rattle issue.

Mike

plncrzy

I will try 92 octane and see.but I dont think its a octane issue when the rattle is mostly from deceleration.. and its definitely a mechanical rattle and not pinging.


as for my truck and the gear running at 50mph.. I should have been more explicit;

1. It used to run no issues in 10th gear in same road that that travel weekly.
2. As soon as I decelerate it falls to 10'th.. then if I put on cruise and accelerate it stays in 10th.
3. even if I accelerated from 50mph to say 65mph.. it stayed in 7th.

w00t692

It's not an octane issue, if anything the stock tune is doing something with cam timing at light throttle low rpm inputs and it shouldn't be. Cam angle and cam timing can cause misfires on the 5.0 if it's way off, so this is the most likely scenario to me.

And no, i'm not talking about crank vs cam timing, i'm talking about just the duration adjustment via the vct system.