Horible noise from transmission maybe? | Ford Explorer Forums - Serious Explorations

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Horible noise from transmission maybe?


New Member
July 26, 2016
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City, State
Year, Model & Trim Level
1997 Explorer XLT
Anyone have any idea what this is? You can hear the noise at the end of this video,
1997 Explorer, 4.0 SOHC, automatic.

On my way home today this noise just randomly started on the highway, the explorer didn't act like it lost power or was struggling to drive when it happened (although I did quickly pull over to try and see what was up). I didn't see anything leaking or a trail of parts behind me, transmission fluid was still full although it smelled a bit hot maybe? I was only a few miles from home so I decided to try and make it the rest of the way. It shifted into gear fine and accelerated up to speed just fine and without the noise, but when I let off the gas and started to slow down the noise would start again.
When I got home I drove it up on the ramps so I could take a look under it and when I backed down I noticed it made the noise in reverse as well, video is from right after that.

If its a 4x4 I would suspect the transfer case, if its ok it could be the transmission. Pull the pan down to check for debris in the pan.

Transfer case.

First off, I apologize to JK080 and drdoom for not thanking them for their replies sooner. I haven't spent much time working on the explorer between when I posted and now, it had been hot and since I have another vehicle to drive while the explorer is down I was able to choose to not work in the heat.

I was able to pick up a '98 explorer with a broken 4.0 SOHC (valves met the pistons). The guy had pulled the engine, took it apart, bought all the parts to rebuild it, then decided he didn't know how, so I picked it up including all the new parts for $800. I figured if I can rebuild the engine its probably worth it, its only a matter of time before mine will need it, my '97 has 270,000 miles on it. Or fix it and have a spare explorer since other than the engine it was in pretty good shape, but that's a project for another day.

Problem is, although I read up on the differences (or mostly lack of) between the 97 and 98 engines, I didn't do my homework on if the '97 and '98 transfer cases are different.... and they are, on the rear. '97's have the vehicle speed sensor on the back output of the transfer case, '98 they moved off the transfer case and to the rear end... (bolded to stand out in case anyone in the future comes across this so hopefully they wont make the same mistake I did :p)

I've since been trying to do a bit more research on here, reading other threads, and reading http://www.explorerforum.com/forums...rner-4405-transfer-case-rebuild-diary.182071/
From what I could tell, and please correct me if I'm wrong, other than where the speed sensor (and hole for it) are on the back half of the case the '97's and '98's seem pretty much the same. So my idea was to crack open both cases and see if I was right and if I could just swap the rear part of the '97 case with the one on the '98 keeping all the '98 internals (minus the bit in the rear by the magnet and the speed sensor). I figured this would also give me a chance to take a peak into the one I am trying to use as a replacement to make sure it isn't worse than the one its replacing. I pulled both cases apart today and this is what I found:

'97 Transfer Case, when I pulled the back off I pulled it straight up as best as I could to avoid bending/breaking that pin at the bottom of the ramp/cam for the shift fork but I must have been slightly crooked because that piece came with it a little ways then fell back into the case.
There was also a bit of metal shavings stuck to the magnet above the pickup tube, but I'm not too sure where they came from yet.

This is the ramp/cam piece I was talking about, it doesn't look like its in very good shape and it looks like it has a few cracks. Is this bad enough to have been causing the issue?

The holes on the back half of the case which that piece and the shift fork go into still look round

But on the side of the one the rod for the ramp/cam piece goes into it looks like there is some cracks, are these going to cause me issues if I reused this half of the case?

The shift fork its self didn't look too bad, it wasn't cracked and missing the guides like the one in the rebuild diary anyways.

I did not get a good picture of the '98 after I took the case halves apart, but I was able to pull them apart this time without the ramp piece coming out.

However, I did pull it out after by lifting up on it and the shift fork at the same time until the pin at the bottom of the ramp/cam came out of its hole. On the '97 the ramp moved up and down the shaft it was on a little ways, I wanted to see if this one did it too since I don't know if its supposed to, it did as well. Is the ramp piece supposed to slide a bit on that shaft?

Video of the movement on the one from the '97 I was talking about,

This is the hole the pin goes in on the 98.

And the shift fork on the 98.

I didn't take either of them apart more than this tonight, I kind of wanted to see what the thoughts here might be. Do the parts in the 97 case look bad enough to possibly be causing the issue I was having? Is that ramp that moves the shift fork supposed to slide like it is? Is it possible to put the rear of the '97s case on the '98, and are the cracks in the side of the hole the cam assembly slides into going to cause me issues?