Strange slipping/grinding, goes away on restart

[toddious]

I have been having an intermittent issue arise while driving my 2004 v8 Explorer recently.

The issue seems to arise when I'm driving in traffic and in around 2nd-3rd gear. A grinding/vibration will show up out of nowhere and it will feel like the transmission or clutch is slipping. At first I thought it was a wheel bearing issue because it has a sort of grinding to it.

The weird thing is that if I pull over, shut off the car, and then start driving again the issue will be gone. It will only show itself again when there is alot of shifting accelerating/decelerating while in 2nd-3rd gear (while stuck in traffic, etc).

I originally though transmission issue, but the fact it goes away when I shut off the vehicle is really strange to me. Any ideas?

There are no check engine lights or anything coming on when this happens. It just drives really bad.

Thanks in advance for any advice.

 

[TTSport15]

im guessing this is a standard trans,,,have you checked the fluid?

 

[toddious]

I had the truck at a shop over the weekend and they checked all fluids. The issue didn't pop up on their test drive so they couldn't troubleshoot. I'm wondering if it is throttle or maybe a timing issue?

The weird thing is that it goes away when you shut off the vehicle. Could it be an issue with the transmission if that's the case? Or maybe computer/trans issue?

I don't know where to start. Any help is appreciated.

 

[toddious]

I'm wondering if anyone else can chime in.

The vehicle is currently at a transmission shop but they couldn't seem to find a transmission problem with any of their tests. They are thinking it could be the transfer case. The issue seems to pop up when you try to accelerate and the transmission is between gears. I'm still confused that the issue will go away after you restart the engine.

Any ideas? Could this be transfer case? They want $350 to remove and test it. I'm not convinced that this is the issue. I've never heard of an issue like this (vibration/grinding) that goes away from restarting. Could it be a computer issue to the transmission or transfer case?

 

[apenland01]

computer reset

You can reset your PCM for free. It may not help, but it will reset everything and force the PCM and tranny to relearn shifting. If nothing else it may cause it to throw a code if there is indeed some problem you aren't finding.

Paying anyone $350 to give you a guess test is crazy in my opinion, but that's just me.

To reset your PCM, follow the instructions from Makuloco2000 on youtube.

It will take a full week for your Explorer to relearn everything and settle down, at least I know mine does with my driving style.

If it's still doing it after the reset, then you can start looking at other things, but this way you can rule out the PCM causing issues for free.

 

[toddious]

Thanks for the reply, and that might not be a bad idea to consider anyway since this is a used car I just recently purchase. Would probably rather "start from scratch" and have it learn my driving anyway.

I have also read about different tire tread potentially causing an issue with the 4wd auto in the transfer case. I do have different types of tires in the front/rear, but they are at the same tread point. COuld this cause an issue like this? and if so, would it go away on restart?

I'm thinking this could be a possibility, like the transfer case sees different rotation, then kicks on the 4wd, and when I shut off and restart it stays off until triggered again? It's just weird then that this only happens sometimes, and after being a specific type of shifting/acceleration.

I'm at a loss, and agree that it seems nuts to spend $350 just to have them remove the transfer case and open it up without being sure that's the actual problem.

 

[apenland01]

I do know there are tire issues that can cause a transfer case problem, although I've never experienced it on mine. I get all 4 tires at the same time.

Again, start with resetting the PCM and then consider your options. Things like tires are something you are going to have to replace down the road anyway, so it can be a good thing to replace them before breaking into all the mechanical stuff. $350 is almost the cost of a cheap set of 4 new tires.

 

[toddious]

OK, so I definitely wanted to give an update on this in the hopes that it may help someone else in the future:

So the issue ended up being the tires on my truck. When I purchase the vehicle the front tires had some uneven wear, so I had an alignment done and I purchased 2 used tires with the same level of tread as the back tires. HOWEVER - although these new tires (Goodyear Fortera) were the same sizing and visibly had the same amount of wear as the back tires (off-brand), they apparently did not have the same rolling circumference. This was fooling the "Auto 4x4" into thinking that the tires were slipping, causing the transfer case to kick in the front wheels. I'm assuming that's why the issue was resolved when the vehicle was shut off, since it would no longer sense the slipping.

Seeing as how the Goodyears I had bought were about 50% tread, I went to a used tire shop and had them put on two matching Goodyear Fortera's with the same level of tread, and the issue has gone away completely. I've never had auto 4x4 before, so this was something I had never really considered. Once these tires are a little lower I will splurge for a complete new set.

I'm still considering doing the Brown Wire Mod to just do away with the auto 4x4, so that I can just turn on the 4x4 option when I need/want it, and leave it in 2wd the rest of the time.

In the meantime I still plan to do the PCM reset since this vehicle is new to me, so I might as well have it "learn" my driving habits.

Thanks everyone for the help. Hopefully my experience may save someone else some trouble.

 

[apenland01]

Awesome!

OK, so I definitely wanted to give an update on this in the hopes that it may help someone else in the future:

So the issue ended up being the tires on my truck. When I purchase the vehicle the front tires had some uneven wear, so I had an alignment done and I purchased 2 used tires with the same level of tread as the back tires. HOWEVER - although these new tires (Goodyear Fortera) were the same sizing and visibly had the same amount of wear as the back tires (off-brand), they apparently did not have the same rolling circumference. This was fooling the "Auto 4x4" into thinking that the tires were slipping, causing the transfer case to kick in the front wheels. I'm assuming that's why the issue was resolved when the vehicle was shut off, since it would no longer sense the slipping.

Seeing as how the Goodyears I had bought were about 50% tread, I went to a used tire shop and had them put on two matching Goodyear Fortera's with the same level of tread, and the issue has gone away completely. I've never had auto 4x4 before, so this was something I had never really considered. Once these tires are a little lower I will splurge for a complete new set.

I'm still considering doing the Brown Wire Mod to just do away with the auto 4x4, so that I can just turn on the 4x4 option when I need/want it, and leave it in 2wd the rest of the time.

In the meantime I still plan to do the PCM reset since this vehicle is new to me, so I might as well have it "learn" my driving habits.

Thanks everyone for the help. Hopefully my experience may save someone else some trouble.

Thanks a lot for looping back and providing an update! It sounds like this is an happens often and it is a common question on the board.