Elephant

Hey Guys,

Last night I remote started my 2007 F150 2wd 5.4 with 140k miles and was hearing a weird rattling noise, like a low-pitched exhaust rattle. I got in, put it in reverse, and it wouldn't idle (as in: move forward on it's own. I am NOT talking about the engine RPM idle) in reverse. Gave it a little throttle and it suddenly jumped into gear and lurched backward. Went into drive and exact same thing. I limped it home but off the line it would do the same thing. On the way home, I lost ability to accelerate...engine revs did nothing, but then it came back. Seemed to happen in all gears but I can't pinpoint that 100%. Taking it out of OD didn't seem to have any affect.

For a little history, starting about 3 years ago I was idling in 3 hours of gridlock in Houston (18-wheeler overturned on a major freeway during rush hour) in 100-degree weather and my AC started getting hot and I got a "transmission malfunction" warning. My temps were 210 when normally it's at 150 ish. Ever since then, excessive idling will have it approach that same level.
Flushed transmission when I first got that fault, replaced diverter valve as well as filter. No real change.

It's been giving me no problems other than higher temps for 3 years. Now I get what happened last night. I'm thinking torque converter but everything I know and read about them indicates I should be getting LESS slip and more stress on the brakes when I'm at a stop...not a lack of ability to idle forward.

Any ideas?

My to-do list when I get home: check for codes (even though no trouble lights) and revert my Gryphon back to stock tune. If those are negative, I will unhook the battery to reset the computer.

BadFish523

Honestly to me it sounds more like a timing problem.


https://www.f150forum.com/f4/final-r...-sound-141266/


Id check for codes. The timing issue is very common and fairly easy to identify if you do some research. Poor idle, rattling on cold start, diesel sounding knock at warm temp below 1200 rpm. Check this out and maybe this is your problem. Unless it has a tranny code. Or you're sure its a tranny problem.

Elephant

Thanks for the suggestions! I'm aware of that problem but unfortunately don't get anything resembling a diesel sound nor any sort of a rough idle. I'll double check that when I get home from work as well though. I don't want to rule anything out yet!

I also edited my original post to clarify that when I said it won't idle in reverse, I mean the engine idles smoothly, just won't move at ~3mph like most vehicles do when you aren't on the brake or gas.

BadFish523

Sounds tricky. So if you hit the gas while moving forward the engine will rev up but the truck wont speed up? Like the transmission is slipping? Or when you give it gas it just seems gutless?

Elephant

The former. Won't move until it hits a certain rev then it suddenly jumps in. Until yesterday, when I would go from park to D, I could feel the truck lurch (power applied to the drive shaft, brakes holding me in place) as it should. Now it doesn't do that in D or R.

Torque converter? Could it mess up to where it's slipping too much or when torque converters fail do they ONLY tend to lock up?

BadFish523

I cant help with that. Someone on here can though. I'm sure of that! Sooooo much knowledge on here its ridiculous! Just give it time and list as many details as you can to help narrow the problem down. Sorry I couldn't help, hope you get an answer quickly.

vintageman

I gotta ask, when you checked the fluid level, was the vehicle in Park or Neutral? It should be checked in Park, when the vehicle is in Neutral and the Trans Fluid level is checked, it will be about an inch higher on the dipstick and therefore give a false reading that the fluid is full. To me, the situation sounds fluid related, what type of trans fluid did you use?

Elephant

I checked it in park. The fluid is at the "cold" level with a hot transmission. I will go ahead and top it off to be sure. I honestly can't remember what fluid I used. It was about 2 years ago.

More diagnostics: no trouble lights, no codes, returned to stock programming, and no difference.

Off the line under heavy acceleration it's definitely slipping then shudders as it tries to really catch the gear. If I stay on the accelerator, it just keeps shuddering until I let off and it'll catch. Does this with or without OD on and does the same behavior in reverse.

Also at high speed in a particular gear, I get a squeal that sounds sort of like tires squealing but also sounds slightly metallic.

I'm really leaning toward TC right now but could that explain why my temps are rising so fast (200+ just driving around the neighborhood)? Do they share fluid?

Mod (Ret.)

At this point, I'm betting the transmission fluid is toast, meaning it has been burnt due to the slipping, and has lost much of its additives. Might be time to get a real transmission diagnosis at a reputable transmission shop.

Its rare for any certified transmission specialist to chime in and diagnose your fault(s) on these forums unfortunately.

Elephant

Well unfortunately I didn't find anything good today. I drained about 5 quarts from the cooler supply line then dropped the pan. Found a lot of metal pieces in the pan. A few of them are from a small rod like 1/16" diameter...roller bearings?

Cleaned out pan, replaced filter, added 7 quarts of fluid to get it to full. Started driving around the block and it did ok then all of a sudden a nasty grinding noise while idling forward. Sounded like worn brake pads making grooves in the rotors. Did this in forward or reverse. I got out and walked next to it (while my FIL drove) and its definitely coming from the trans area. It got so bad I couldnt even get up the driveway at my house until I about floored it.

Looks like I'll begin my research of rebuilt transmissions and determine if I have time to do it being my daily driver...