I am finally done with my 74 40 series. I was/am planning on taking it to inspection today hoping it will pass so I can register it. Last night I was putting around the neighborhood when I started to notice a squealing noise, the noise has been there in the past but never payed much attention to it. I crawled under the truck and noticed the noise was coming from the clutch area. I pulled the cover assuming it was the throwout bearing, it's new but that's what it sounded like. After inspection I noticed the noise appeared to be coming from the flywheel. At least that's what it sounded like. The clutch feels normal and all the clutch parts are new aside from the pressure plate. All bearings are new. From what I read on others post it may be a tranny bearing but I'm not sure. There is a small leak in the front of the tranny.. It's small enough that it will run a bead of gear oil down the from of the tranny but not big enough to drip. Any thoughts or ideas would be appreciated.. Thanks
Squealing Noise Mystery
- Thread starter mruff
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LAMBCRUSHER
SILVER Star
could be the input shaft bearing on the transmission. do you notice the noise when you have your foot on the clutch? If not, then I would continue to question the transmission. If you have the noise regardless of clutch position, then I would stay forward of the transmission.
Mine started making a light squeal noise shortly before it seized up due to lack of oil pressure. Sounded identical to a belt squeal and went away with a little throttle, it was only at idle. Is your oil pressure gauge operational and showing pressure?
- Thread starter
- #4
Have great oil pressure. I'll check to see if the squel changes with clutch position. If I drive it like this is there any reproductions other than smoking the bearing. I have a spare tranny but am kind of sick of working on it for now and just want to enjoy it for a couple of weeks
LAMBCRUSHER
SILVER Star
how loud is it? is there an accompanying vibration or any grinding sound? YMMV!!!
- Thread starter
- #6
It's noticeably loud. I played around with it and noticed the squeal doesn't change with the clutch engaged or not. No grinding noises that I can tell.. Doesn't seem to speed up or slow down with RPM's
- Thread starter
- #9
It's not original to the truck but original to the motor. It's a 3 speed floor shift...
Ok, so I think I have this same issue. To be clear, the whine for me only happens when I push down on the clutch pedal (in neutral and when shifting). I've been commuting with mine a lot more lately and in the last week the noise started happening. From what I've gathered from this post and many others, it's the pilot bearing, right? I've also been forced to pull out the choke a bit to keep it from stalling (related?)
I plan on replacing it myself and have found other posts with some good lists of other things I should be replacing at the same time (throw out bearing, rear main seal...)
My other question for now is how much time I have before it becomes critical to change it and what are the risks at this point? I can probably get around to it in the next 2 weeks but I kinda need to be driving it about 20 miles per day before then in Chicago stop/go traffic. Otherwise, the clutch is working just fine.
Thanks,
Tim
I plan on replacing it myself and have found other posts with some good lists of other things I should be replacing at the same time (throw out bearing, rear main seal...)
My other question for now is how much time I have before it becomes critical to change it and what are the risks at this point? I can probably get around to it in the next 2 weeks but I kinda need to be driving it about 20 miles per day before then in Chicago stop/go traffic. Otherwise, the clutch is working just fine.
Thanks,
Tim
Not the pilot bearing, the throw-out bearing. If you need to drive it, just don't ride the clutch. Shift into neutral and let the clutch out. I'd guess it should last two weeks, but don't whine (pun) if it doesn't.
Unless it's been done recently, I'd also do the pilot bearing, clutch and pressure plate and have the flywheel surfaced, as well as the main bearing seal and maybe the tranny input shaft seal.
A new pilot bearing will be stiff for a few hundred miles making you think all kinds of weird stuff is going on.
Unless it's been done recently, I'd also do the pilot bearing, clutch and pressure plate and have the flywheel surfaced, as well as the main bearing seal and maybe the tranny input shaft seal.
A new pilot bearing will be stiff for a few hundred miles making you think all kinds of weird stuff is going on.
Thanks for the clarification on which bearing. The more I think about this the more I realize that if I'm going to do this I should probably just drop the extra $ and replace the clutch and pressure plate. Thanks for the list of other parts. I doubt that any of these parts have been touched in decades.
I've been shifting into neutral as much as possible mostly without using the clutch at all knowing it would probably prevent additional damage (and avoid hearing what sounds like a low volume police siren every time I shift!)
I've been shifting into neutral as much as possible mostly without using the clutch at all knowing it would probably prevent additional damage (and avoid hearing what sounds like a low volume police siren every time I shift!)
So, my throwout bearing was in rough shape and the pilot bearing had disintegrated. One of the reasons (besides age), seemed to be that the boot on the non-clutch side had slipped off. It was actually somehow hung up further back near the exhaust! So, a whole lot of crud has made it's way in there.
A couple questions as my manual is crap on details:
1. Where is the rear main seal located? (I'm guessing behind the flywheel?)
2. Do I have to drain the engine oil for #1?
3. Where is the tranny input shaft seal located? (I'm still in the process of cleaning it and it's hard to see through the gunk on all this stuff)
4. Any tips on getting the outer ring/band of the pilot bearing out (the rest of it just fell out onto the ground) I think the bread technique is only meant for a bearing that is still somewhat intact.
A couple questions as my manual is crap on details:
1. Where is the rear main seal located? (I'm guessing behind the flywheel?)
2. Do I have to drain the engine oil for #1?
3. Where is the tranny input shaft seal located? (I'm still in the process of cleaning it and it's hard to see through the gunk on all this stuff)
4. Any tips on getting the outer ring/band of the pilot bearing out (the rest of it just fell out onto the ground) I think the bread technique is only meant for a bearing that is still somewhat intact.
Found this for the rear main seal (questions 1 and 2):
https://forum.ih8mud.com/40-55-series-tech/78749-oil-pan-side-cover-gasket-stuff-faq.html
https://forum.ih8mud.com/40-55-series-tech/78749-oil-pan-side-cover-gasket-stuff-faq.html
Sorry to drudge up this old thread, but I'm about at my wits end! What you described in the attached message is exactly the same thing that is happening to my 74 FJ40. I assumed it was the pilot bearing, so dropped transmission and did a complete clutch rebuild. Put everything back together and the squeal is still there, louder than ever! Did you ever figure out the issue with your FJ?
