Hey fellas,

My friend dropped off his truck to recently troubleshoot an on/off problem he has been having with it. 96CCLB with an e40d. Out of the blue the truck will barely move in 1st or reverse. Other times it drives just like it did before, problem free. At one point it was near impossible to get in and out of 4wd LO too, and wasn't an issue of locking the hubs or bound shift linkage, not sure if this stemmed from the issue or is another issue in itself.

To me it simply sounds like the converter is not locking up, due to lack of line pressure or the converter shatting the bed. The randomness of the issue is throwing me for a loop. I have rebuilt quite a few older 4R100s and a few C6s but have not opened an e40D up. I have searched and have found all sorts of comments towards different sensors/solenoid packs, but this sounds simply like a converter or sensor. Are they known to have range position sensors to fail? Is there a way to overide the line pressure like a 4r100 to test he converter. I'm all ears and wanted to help a friend out before I tell him to run it down to a tranny shop. I was hoping it may be something simple and electronic. OD has never blinked either. Issue is at random. I have been unable to replicate it in the last few evenings but he has showed me short video on the job site of the problem.

Sorry for the vagueness of the question, I figured they may be a few experienced guys out there who may have advice on a couple quick checks before he has to pay the big bucks for the fix.

Thanks!

 

If the torque converter were to lock it would stall the engine. The converter should not lock below about 40 mph.

There is no sensor or anything electronic that could cause this. It HAS to be something mechanical. If you can rebuild 4 100 you can rebuild an E4OD. They are almost identical inside.

 

Agreed. I may have misworded what I intended to say. Simply wasn't sure if there was a way to overide line pressure in an e40d to lock the converter was all. I have heard of it, but wasn't sure.

That being said I was able to get it to replicate symptoms last night. I will say its quite odd and I feel as if its actually not fullt shifting between gears. I was on approximately 30 degree long slope and when in neutral or reverse it would not back downhill.... that was weird. Its as if it never made the transition from drive to reverse or neutral... but was stuck somewhere in between. His fluid is toast too. He is going to have it flushed with a new filter just to see what happens, but I doubt that is it.

I have been reading quite a bit on how the Manual Lever Position/Transmission Range (MLP/TR) Sensor can effect operation of the e40d... No current stored codes either.

I didn't realize this was the second motor in this truck, first cavitated a cyclinder wall out, and this is the original transmission from the factory. You can believe me or not, but the trans has near 390,000 miles on it. He bought it brand new and never has replaced the tranny. I'd say its about time for a new one, unfortunately his hours at work have shortened up and a new trans or full rebuild is financially out of the question at the moment. We have a couple fleet trucks that will be sold off early next year that have factory replacements in them with less than 30k on the clock. I'm hoping to be able to get him by till we can purchase a parts truck and simply swap. Otherwise I can't see anything else besides a full rebuild or throw a RPS at it with high hopes. I'm just trying to help the guy out. I currently don't have the capacity in my schedule to do the rebuild either, I'm overwhelmed multiple motor builds on top of my real job... no time...

 

I'll tell you what will happen. He will have wasted his money on this. That's the best case. The trans could also die right after, but it would have died without the new fluid, too. This is like a tire with a 6" spike through the sidewall. Putting a piece of duct tape over it may reduce the hissing noise, but the tire is done. So is this transmission.

Randomly throwing parts at it that in no way can help surely isn't helping the guy out. It's just wasting his money, which you already said is tight.

 

My understanding is that a TRS will not cause a trans to not engage a gear. But can mess with shifting

 

Agree with you fully on both statements. I let him know exactly that, and its up to him. Bandaiding the problem won't fix it, however his rig is also how he makes his living, so not having the truck for a week is not an option. Spoke to him on he phone and from the sound of it he maybe taking out a loan to pull it and fix it correctly.

That being said since you are a tranny engineer, if someone brought a trans to you with these symptoms without any sort of diagnostic codes(confirmed by as reputable trans shop), what would you do? Like I said the problem is intermittent. You claim its solely mechanical and not a sensor, what makes you believe this? Sounds more electrical/sensor to me than mechanical. I only ask since I am trying to help a friend out that doesn't have the funds for for parts, let alone labor, until work picks back up. He can only make the money to fix the truck if the truck is running, or borrow and payback later.

Once again, I'm not throwing parts and fluid at the effn thing in hopes of fixing it. He would like to change the fluid, and my comment of throwing RPS was in leu of the fact they can cause quite a few issues from what I have read, issues similar to what he is experiencing. That's why I'm on here asking if others have experienced this problem or not. If its worth changing or not. I have an e40d behind a 460 and was wondering if it would be worth swapping the sensor, only if its the same. That is why I got on here to see if it was even worth the time or not. Guys who know these transmissions well enough like those who know a 7.3 can usually diagnose fairly quick off symptoms. So that is why I asked.

Thanks!

 

Because there is nothing electrical, nor any sensor, that will keep it from moving in first or reverse.

I think there are seals that are torn or worn and intermittently not sealing correctly. It might be the feed bolts under the valve body, but since the fluid is toasted that almost always means the trans is toasted.

 

Good to know. Thank you for your help.