Flywheel Fiasco

[renjaminfrankln]

Sooo... I posted awhile back about possibly needing to swap out some motor mounts due to a rattle, which was quickly (and correctly) diagnosed by the membership here as a bad dual mass flywheel in my '89 7.3 4x4 with ZF5 transmission. (rattles and clunks with the clutch let out in neutral, rattle goes away when clutch pressed in)

I brought it to the local transmission shop and showed them the rattle, that I thought it was a bad flywheel, they agreed. They quoted me 6.5hrs labor to throw in whatever kit I wanted. A member here recommended LUK 07225 kit which he apparently installed on his '91. The transmission shop guy agreed that kit would work (I called and read him the part number). HOWEVER - rock auto sells the kit but did not list this kit under the options for my truck.

Well I get a call from the shop telling me the kit I bought does not fit, something about the release bearing being the wrong size. However, the guy proceeds to tell me that the truck has already been converted to a single mass flywheel, my pilot bearing is shot, and they can get me a new clutch and bearing from carquest that will work with my original flywheel. I said, okay - go for it. Figuring that the trashed bearing was the cause of the rattle.

I get the truck back today, and unfortunately the rattle is still there (although the clutch feels fantastic now with the new pilot bearing). So I bring it straight back to the shop... we do some poking around (remove access cover) and lo and behold, there is a totally worn out DMF in there...

The shop manager owned up to the mistake and told me to find him a flywheel, set up a date and they'd install it for free. I said okay. Now that brings up some questions...

Are there any single mass flywheels that will work with the stock clutch. Do I even want this considering the stock clutch may not be dampened? Probably not.

Can I find a good dual mass flywheel anywhere for a reasonable price? Everything I see is aftermarket single mass. I would not mind buying one at this point if its less than $300 or so, the clutch is really smooth now...

 

[towcat]

years ago, I used to clean up on good used dual mass flywheels due to misdiagnosis. unless you are missing springs on your dual mass flywheel, be absolutely sure your injection system is in top shape before condemming a flywheel. often a lazy injector will cause a flywheel to go ******* due to the compression ratio these motors have.

 

[renjaminfrankln]

years ago, I used to clean up on good used dual mass flywheels due to misdiagnosis. unless you are missing springs on your dual mass flywheel, be absolutely sure your injection system is in top shape before condemming a flywheel. often a lazy injector will cause a flywheel to go ******* due to the compression ratio these motors have.

We pulled the inspection cover and it has a ton of play.

 

[BrianX128]

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Is it better or worse than mine?

I can't even find a shop willing to touch mine in western PA. No one wants to do the work the moment I mention it would be a SMF conversion. Not sure how I'm gonna get mine repaired, I have a bad rotator cuff from baseball in my good arm (lefty) and don't have a lift or any automotively inclined friends to help (everyone runs when I say help me get the trans out of my truck)

I've just kept driving it. Hasn't gotten any worse in 10k miles...

Wish I could find a reputable shop near my area to fix this, got everything done with the truck I wanted and found that a week before the rally..

 

[renjaminfrankln]

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Is it better or worse than mine?

I can't even find a shop willing to touch mine in western PA. No one wants to do the work the moment I mention it would be a SMF conversion. Not sure how I'm gonna get mine repaired, I have a bad rotator cuff from baseball in my good arm (lefty) and don't have a lift or any automotively inclined friends to help (everyone runs when I say help me get the trans out of my truck)

I've just kept driving it. Hasn't gotten any worse in 10k miles...

Wish I could find a reputable shop near my area to fix this, got everything done with the truck I wanted and found that a week before the rally..

Looks about like mine does!

FYI the shop that is working on mine charged $700 labor, they would probably be considerably less for a 2wd.

 

[Thewespaul]

Texas is right there next to pa, you could always bring it to me

At the age that these trucks are now, I have yet to see a dmf that isn’t missing springs and has half a mile of play.

 

[renjaminfrankln]

Texas is right there next to pa, you could always bring it to me

At the age that these trucks are now, I have yet to see a dmf that isn’t missing springs and has half a mile of play.

I went ahead and ordered a precision kit from carquest for the conversion... $280 shipped on rock auto. Has the 12" flywheel and the clutch is dampened with two sets of springs. Shop says they'll return the clutch I paid for and credit me back.

Both advance auto and rockauto sites say it will fit my truck, so fingers crossed.

 

[towcat]

i have that much play in mime and still go cross country round trip at least once a year.

 

[renjaminfrankln]

A member here recommended LUK 07225 kit which he apparently installed on his '91. The transmission shop guy agreed that kit would work (I called and read him the part number). HOWEVER - rock auto sells the kit but did not list this kit under the options for my truck.

The saga continues.

Rock auto does list the 07225 Luk kit as fitting my '89 F250 4x4 w ZF5. It is in "clutch kits" not "flywheel conversion kits" where I was originally looking. In addition, I found another site, partsgeek, lists this kit as fitting 88-94 models.

So, now I have two clutch kits sitting in my garage and it appears the problem is that the transmission shop mechanic just screwed up. he said the release bearing was incorrect. But I do not know that he actually tried to put everything together. It is entirely possible he compared it to the stock release bearing, it was different, and so he said "this kit is wrong"...

Is there any way that this kit does not fit my truck? Is it possible there are two versions of the ZF5 in the same year? Because i'm about to make them re-do this job and I don't want to be wrong.

 

[Thewespaul]

No, you have the correct kit.

 

[renjaminfrankln]

Thanks. I'm going to make them give me a 6 pack and a lawn chair so I can supervise this time.

 

[renjaminfrankln]

Alright.

So I know the SMF is supposed to chatter and grind a bit if you are lugging it. I took this to mean that, if you let the clutch out and try to drive around at under 1100 or so, you'll get some noise.

Mine is making a grinding noise at idle, in neutral with the clutch in or out. Goes up/down with RPM. Put in gear, let out clutch, the grinding noise goes away almost immediately upon acceleration through each gear, then comes back as the RPM's wind down between gears (till the next gear catches).

Driving, with the clutch out, say 1800 RPM, it makes this noise LOUD at either neutral throttle (maintaining speed) or decelerating. It goes away completely under hard acceleration, and the truck is quiet and smooth like it used to be, under acceleration anywhere in the RPM range.

Is this normal for a single mass flywheel, or did they screw this up again. Noise and vibration at highway speed is doubled. Unless i'm accelerating, then the noise goes away.


In the video below, you can hear it go away as I get on the throttle around :14 in

Then as I shift through two gears later, its silent when accelerating through each gear, then the noise comes back when the clutch is pushed in and the RPM is dropping for the next gear.

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[renjaminfrankln]

Another video. Under acceleration - no problem. Deceleration, sounds like it has a damn jake brake on there.

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[franklin2]

That is a deep hollow sound, not the sound I am used to from a SMF flywheel. I don't know what that is, are you sure you do not have a exhaust leak?

I will also say your engine doesn't idle very smooth. Sounds to me like a cylinder is down on it, it has a little lope to it.

That's the problem with the SMF conversion, anything happening with the engine is amplified into the aluminum transmission.

P.S. I bet I know why the other poster cannot get anyone to do a SMF conversion in his area. They have had too many unhappy customers with the noise that the SMF generates.

 

[renjaminfrankln]

That is a deep hollow sound, not the sound I am used to from a SMF flywheel. I don't know what that is, are you sure you do not have a exhaust leak?

I will also say your engine doesn't idle very smooth. Sounds to me like a cylinder is down on it, it has a little lope to it.

That's the problem with the SMF conversion, anything happening with the engine is amplified into the aluminum transmission.

P.S. I bet I know why the other poster cannot get anyone to do a SMF conversion in his area. They have had too many unhappy customers with the noise that the SMF generates.

Well, if that is the case I need to find a usable DMF. But, I have never heard anyone explain the added noise from a SMF as what I am experiencing. It makes a ton of racket every time I let off the throttle. Under acceleration, quiet and smooth. It is also twice as loud when cruising on the highway. Everyone complains about vibration at low RPM, lugging it with the clutch out. I have none of that if I am on the throttle. At a stop, in neutral, it goes from loud/grinding noise at idle in neutral to quiet and smooth when I let the clutch out and accelerate away from a stop. This seems to be the opposite of what most people report.

The sound that you might think is an exhaust roar (when decelerating) is all vibration from the transmission. My exhaust is new, muffled and there is only one minor leak behind the turbo, which you only hear as a "**** **** ****" under heavy acceleration. The video does a terrible job conveying vibration.

It is possible I have a lazy injector. They are new, but they are also from Pensacola diesel... i also would not expect that to make the transmission grind when completely off the throttle at 2000 rpm. It was completely smooth before.