Does this make sense?

[demarpaint]

I've been getting an annoying clutch chatter from my 88 Ford E-150 for a very long time now, its a work truck and I ignore it for the most part. I've tested the clutch for slippage but I can't get the clutch to slip no matter how hard I try.

Some quick history about the van, the clutch is a heavy duty Center Force II clutch well over 20 years old with about 65,000 miles on it. 95% of its use has been a fully loaded van stop and go use.

What I find odd is this: Lets say I use the van Tuesday-Friday. The longer the van sits the better the clutch feels. Tuesday morning the clutch is perfect, by Thursday the chatter is there and pronounced, and Friday its a bit worse. This behavior is consistent and predictable.

I was talking about this today with my brother and he thinks the clutch is glazed. He feels that the days the van sits unused the flywheel gets a bit of flash rusting, and its that flash rusting that is eliminating the chatter. As the clutch grabs the flywheel it gradually removes the rust and that's when the chattering starts again. It actually makes sense, but I don't think the flash rusting would hang around that long. Any ideas are appreciated.

I'll probably replace the clutch at some point, but thought I'd toss this out to you guys. Thanks.

 

[NHGUY]

Yup could be rust.Could also be the slave cylinder is getting too "pumped up" with multiple pedal strokes,keeping pressure on the slave/bearing/cover.Maybe a master thats not allowing full fluid flow back into the reservoir?

 

[TechnoLoGs]

Quote:
The longer the van sits the better the clutch feels.


demarpaint, my very first guess, based on reading that description, is some kind of massive heat buildup that takes a looooooong time to dissipate. Possibly even some ind of lubrication issue, where the longer it sits, the better it feels - until it starts to overheat, and get very very hot.

I have had Hyundai Excel transmissions that only worked (engaged, moved car forward/backwards) if they sat for 4 days or so. Then they would heat up and not engage and act in neutral in all gears.

This preponderance could be wrong, but, again, first thought.

 

[GreeCguy]

I doubt rust as just a few days of light rust would be wiped off with just a few shifts, especially in stop and go traffic and if you ride the clutch.

How about your throw out bearing?

 

[GreeCguy]

This comes from a site called "ASE test site"

"Clutch chatter is an excessive vibration felt just as the pedal is being released and the clutch is beginning to engage. To test for this condition set the emergency brake, depress the clutch pedal and rev the engine to about 2000 RPM. Slowly release the pedal so you can feel when the clutch starts to engage. This is the point a clutch will begin to shudder. Clutch chatter is typically caused by glazed or oil contaminated clutch facings. The engine and transmission mounts and alignment dowels should be checked as misalignment will cause major clutch chatter as well as damaging parts."

 

[spasm3]

Does it use a little oil? I was wondering about the rear main seal leaking oil onto the clutch.

 

[andyd]

Its a 25 yr old Ford fer cripes sake. I will be thrilled if the Rat is even running when it is 25. Possible leaky rear main seal contaminating clutch ? I spent waay too much time and money re-habbing the Rat. Now I have a good running ugly old truck.

 

[demarpaint]

The van doesn't use a drop of oil, nor does it leak, not even a drop, so it is safe to rule out oil contamination. I've never had to top of the hydraulics either, so no leaks there.

I doubt it is fluid heating up because if you shut the vehicle off overnight it cools off along with all the fluids. As I mentioned it shifts perfectly and doesn't chatter when it sits over the weekend. The chattering starts about 2-3 days into the week. One thing I forgot to mention is the chattering is not violent, just annoying. The slave cylinder, and TOB are fine, no leaks, and no noises from the TOB, there is also no grinding. The fluid level in the transmission is full. All engine and transmission mounts are fine. As I mentioned I think the clutch is glazed, and I thought my brother's explanation made sense since everything else was ruled out. There are times when it doesn't chatter even towards the end of the week, although it tends to chatter more, after a few days use.

The van is in excellent condition.

Years ago I read that some chatter was considered normal depending on the gear ratio. This was in the mid 80's when they were using 300 rears to save fuel.

Thanks for the replies. As I mentioned I'll probably change the clutch, PP, TOB, pilot bearing, slave cylinder, flywheel, and rear main seal [even though it doesn't leak since I'll have everything apart] at some point this year.

 

[Virtuoso]

Work van? Run that puppy till it slips. JMHO.

Clutch chatter can be quite annoying though. Had an SHO that did that after a clutch replacement. Lady in an Expedition turned in front of me and took care of that problem before I could figure it out, though...

 

[1kickbuttranger]

I had the exact issue on my 5.0 when I got it. Clutch would chatter when first driven if it was driven every day. If it sat for a week or two, it seemed fine. I replaced everything and all was fine. Existing clutch and pp was wasted and had 2 broken dowels.

 

[demarpaint]

Originally Posted By: 1kickbuttranger
I had the exact issue on my 5.0 when I got it. Clutch would chatter when first driven if it was driven every day. If it sat for a week or two, it seemed fine. I replaced everything and all was fine. Existing clutch and pp was wasted and had 2 broken dowels.


Interesting. Just how bad was it chattering, mine really isn't terrible, just annoying. I'm really leaning towards changing it. I have to motivate myself, and then find a slow spell where I won't be using the van for for a few days. I'll do it myself, but I don't want to be pressured because I need the van.

 

[The_Jeff]

I had a redneck mechanic recommend that I park my car into a tree trunk with the e-brake set, engine idling in first gear, then throw out the clutch. Just jump off the pedal and stall it. Whatever was causing the clutch chatter would end.

Darn if it didn't work. This was on my 89 mazda 323.

I wonder if you're hitting a resonant frequency due to shot motor/trans mounts. Maybe if they have holes in the rubber for "comfort" you could fill those up with "window-weld" or your favorite RTV for experimenting.

 

[demarpaint]

Originally Posted By: eljefino
I had a redneck mechanic recommend that I park my car into a tree trunk with the e-brake set, engine idling in first gear, then throw out the clutch. Just jump off the pedal and stall it. Whatever was causing the clutch chatter would end.

Darn if it didn't work. This was on my 89 mazda 323.

I wonder if you're hitting a resonant frequency due to shot motor/trans mounts. Maybe if they have holes in the rubber for "comfort" you could fill those up with "window-weld" or your favorite RTV for experimenting.


I checked all mounts, and had a mechanic check them when the van was recently inspected, and they're fine.

I've intentionally stalled it buy letting the clutch out while my foot was on the brake, and it has helped the situation for a while, but in time it happens again. Maybe I need some serious method of breaking the glaze. I'm a bit confused with your method, are you essentially idling and just sidestepping the clutch with the brakes locked up? I'm willing to give anything a shot before I replace the clutch, it's a job I'm really not looking forward to.

 

[tig1]

Originally Posted By: spasm3
Does it use a little oil? I was wondering about the rear main seal leaking oil onto the clutch.


Yep! That's the first thing you need to look at. If the rear main seal is leaking even slightly it can get on the cluth and and cause chatter.

 

[demarpaint]

Originally Posted By: tig1
Originally Posted By: spasm3
Does it use a little oil? I was wondering about the rear main seal leaking oil onto the clutch.


Yep! That's the first thing you need to look at. If the rear main seal is leaking even slightly it can get on the cluth and and cause chatter.


No oil use, not even a drop. I mentioned it above, for the age of this vehicle it is in fantastic condition.

 

[01rangerxl]

Originally Posted By: andyd
Its a 25 yr old Ford fer cripes sake. I will be thrilled if the Rat is even running when it is 25. Possible leaky rear main seal contaminating clutch ? I spent waay too much time and money re-habbing the Rat. Now I have a good running ugly old truck.


If your Ranger has the M5OD manual, I would bet it will be running and driving at 25 years old pretty easily. Rust will get it first. The engines were all rock solid that year, only the A4LD automatic is a possible weak point and even many of those go well over 200K miles.

 

[demarpaint]

Originally Posted By: 01rangerxl
Originally Posted By: andyd
Its a 25 yr old Ford fer cripes sake. I will be thrilled if the Rat is even running when it is 25. Possible leaky rear main seal contaminating clutch ? I spent waay too much time and money re-habbing the Rat. Now I have a good running ugly old truck.


If your Ranger has the M5OD manual, I would bet it will be running and driving at 25 years old pretty easily. Rust will get it first. The engines were all rock solid that year, only the A4LD automatic is a possible weak point and even many of those go well over 200K miles.


I have the M5OD in my E-150. It has been good to me over the years. I took care of those round plugs at the top of the transmission that were know for leaks many years ago, and its been fine.

I had the A4LD transmission too, it went over 200K with no problems.

As far as rust, I don't have an ounce of it anywhere on this van.

Eljefino has me thinking about creative ways to try and break the glaze, which I think might be the root cause of my chattering problem.

Wouldn't a bad clutch, slip, or grind, or give some indication other than chattering that it's bad? My only symptom is the annoying chatter which seems to start mid week.