Loss of Power: Thoughts on F250, could use some diesel help...
 

2000 F250, 7.3L diesel, automatic transmission, 250.000 miles, we are the original owners

regular filter and fluid changes, standard maintenance stuff (power steering pump, batteries)

Two weeks ago I replaced the glow plugs, all 8. New main battery, the secondary battery tested OK.

Do not know if this matters, took into dealer for safety recall, they were trying to talk us into trading the truck in, claimed it was leaking oil everywhere. After they had it, it did leak oil and we did have to top up the oil. In changing the glow plugs I discovered two valve cover bolts that were loose on the bottom of each side, the remaining bolts were all at full torque. Miraculously the oil leaks have stopped after replacing the glow plugs. Result: beware that Ford dealer.

This summer we were pulling a heavy load up big hills and the transmission got very hot. Had to replace five quarts of fluid. Did not notice any oil anywhere. Checked the fluid level once a month and did not notice any loss.

Went out and picked up about 7.000 pounds of fence posts from a buddy and pulled them on the flatbed, about 3,500 pounds. Truck did not like going up the big hills but made up highway hills and had no issue at low speeds.

My bad, I did not check transmission fluid after this trip.

This morning the truck pulls trailer out of mud and up a little grade with zero issues. Engine sounds good. I load up the trailer with some hand tools and head out. We have a big hill near the property and I have about 3,500 pounds worth of trailer in back. Truck does not want to pick up speed. Loud and we do not get over 30 mph.

Going downhill we get to 60 without issue.

On level ground the truck does not want to hold a speed faster than 50.

Going up the next hill we drop to 30 and struggle. There is an auto parts store there so I stop and check the transmission and there is zero fluid on the stick.

I go in and buy four quarts, including some Lucas treatment, get in truck and head home. Same issues with hills. Get to my driveway and the truck has zero problem going up the hill in second at 20 mph, no struggle no issue, nothing, just pulls strong!

Add four quarts plus one I had at the house. I have some fluid on the stick but I am NOT convinced the transmission fluid is full. I run back and forth and re-check and have the same amount of fluid on the stick. No fluid apparent under the truck. I hook up the OBD reader and do a test run.

Repeat of exactly the same, zero power, trouble going uphill. No codes.

Return home, check transmission, no fluid on ground or visible under truck, fluid showing on stick.

Disconnect truck and head out in truck. No power going up the hill without anything heavier than me in the truck, cannot get over 40mph. Get to top of hill and turn around and truck picks up speed nicely going downhill. No issue going up the driveway.

Again, there are no codes and everything on the OBD reader shows as normal the entire time.

Any thoughts?

Check your anitfreeze, and see if it is Strawberry quick. I have replaced a few transmission coolers (in the rad) that spewed all the trans fluid into the cooling system . Hopefully antifreeze did make it into the trans. Trans fluid has to be going somewhere

I don't think its related to the transmission. Turbo is going south.

That's what I read. Can you check fuel pressure? Most power issues I've dealt with were bad lift pumps, clogged filters/bad fuel or an injector issue.

That truck has a remote Trans cooler in the front, not incorporated into the radiator. Your tranny fluid is going somewhere. If that thing has its original auto trans, (never rebuilt), w/ 250k miles and the kind of use you describe, it's already in the Guinness book of world records for that unit. You finally burned it up towing w/ no fluid.

FWIW, I might be interested in the truck as it is. I'll send you a message.

How much you wanna bet?

I'll bet the pump in the transmission went out. That would also explain no readings on the dipstick.

The turbo is going South? Really? And that's why it's losing transmission fluid?
Better check your muffler bearings too, right?

Hey man, I never claimed I was qualified to answer anything. ;)

Do the diesels not also have a cooler in the rad?I am 100% sure all the big gas trucks have them supplemented with huge external units. I don't do a ton of diesel work, but have seen more than one gas motor ford puke its rad's trans cooler.

Nope. It's remote.

You might want to see if you can find someone with the software program named AutoEnginuity and hopefully they will have the full Ford module or it might pay to buy it. I have the same engine as you and noted a strange stumbling after I bought the truck in 2004 and it was fuel pressure related. The software can run and record what is happening with injectors and any other settings and I had a fuel filter that was needing replacement. I do it once a year now and have had no issues since. I did add an aftermarket Edge tunner, 4 inch exhaust and free flow intake system and when I tow anything I bump up the computer to "race" setting and found I only need 2/3 of the throttle I used to need.

If the turbo was failing it generally will start burning oil due to failing seals so hopefully there is no oil smoke or loss of oil? You should not even feel a 3500 pound trailer as I pull a 36 foot 5th wheel and when it had the race car in it was about 12,000 fully loaded and it still got 14 MPG. I have had a couple of occasions where I had bad diesel and it could be that so did you fill up recently at a new diesel source?

Another item is to check all the connectors to see if the dealer left one loose on purpose to help you want to get rid of the truck.

The final thing it could be is the ICP sensor and see if the connector is full of oil and if so it is failing. I carry a spare as they can fail for no reason and even Ford has had batches of bad ones.

Ford Powerstroke Forum is the place.

Figure out your transmission issue FIRST
Figure out your transmission issue FIRST
Figure out your transmission issue FIRST

Sounds like as tranny issue to me.

Here is the advice to follow. What does the filter look like? Is the engine revving hard but truck not moving like the front pump or torque convertor went out?

I did some additional reading and took another test drive.


No smoke from anywhere.

I do not see any fluids draining out. But, burning the transmission fluid twice in about six months is NOT a good thing and could have driven the transmission south.

Fuel filter has ~300 miles on it.

Problem started today, Truck has basically just been sitting between tow jobs. Wife uses it in the winter to go to work when the weather turns bad. Outside of the Subaru we have been having such good luck with our vehicles these past many years.


Fast Fred: Green is the color of grass, Kermit, and the anti-freeze. Smells like anti-freeze (sickly sweet) not rancid like transmission fluid. I wonder if I boiled some transmission fluid off two weeks ago?


HD: Gosh, I really hope NOT! But this shows as a possibility. My thought is that even without the turbo I should still be able to gain speed going uphill when the pedal is floored.


Vincent: I have never checked fuel pressure. This seems to be another possibility. But there are no codes and this is supposed to throw a code if the lift pump goes bad or if there is an ignition issue or so I read.


Denis: You could likely be correct! Hate to think that one! Expensive possibility! at least five quarts low, 17 required. Yep original, no re-builds. It has been a GREAT truck!


Jared: Interesting thought! Fixed with a re-build or remanufactured unit. Darn it!


Transmission cooler runs in the front of the radiator but they are close together. This model has the intercooler and a pump for moving the transmission fluid, as I understand it.


John: I did try to run around the engine when doing the glow plugs and did not find anything else with issue. The dealer had it about 14 months ago. I carry spare sensors as well but I will not buy them from Ford. Those go bad too quickly. I go onto the big truck guys and use theirs. They last longer and Ford did not make these 7.3L anyway. I might try and find that software! Wonder if my old computer will run it ;-)


So many things point to the transmission. Now I am a bit scared...

I am going to pull her into the garage and take apart the valve covers again. It MIGHT just very well be that the caps on the glow plugs have worked loose. Losing a few cylinders would cause the same issues. I do not smell unburned diesel though so this might not be the right way to go. It is the cheapest thing to do at this stage.

We both noticed how much more power we had after doing the glow plugs. I'll be back!

A quarter million on a Ford transmission behind the diesel is beyond borrowed time. The loss of fluid need sorted before you worry about anything else. Likely the transmission is toast.

If I recall correctly, there are electronic controls on that transmission. When it overheats, it may be going into some type of limp-home mode which you are seeing as loss of power. Or it's just trying to saw itself in half.

**also** We had our Ford down at the dealer for about 8 months because - well, because they were clueless. During that time, the truck picked up a wicked algae contamination in the fuel. Turned the truck into a complete gutless wonder. Ran so bad climbing hills that I thought it wouldn't even go over the Siskiyous to get home. We treated it with a diesel algaecide by filling the tanks (with the correct amount of algaecide added) and running them through the system. Went through a fuel filter about every two weeks for at least 2 months before we cleared it all out.

Had the truck sit most of the summer this year while Steve was gone and the algae has come back so we're on round 2 of the treatment. Caught it early this time. Look for slimy gelatinous stuff in the fuel bowl (always clean the bowl when changin the filter) and an odd blackish color to the filter.

Ours is a 97 7.3. Trust me, you damn near can't kill the engine itself.

angela

Rats! Looking up pulling the transmission filter. And I wanted a new spoon for Christmas!

Like my dodge tran. I believe they have a safe mode. which basicaslly keeps them in third gear all the time.

One more post: I just noticed there is a fluid seepage at the joining of the driveshaft and the rear differential. Glad this is just a 2wd....

Where would one go about getting a transmission? Wonder if I could put it in myself?