Tranny shop said ZF chatter can be eliminated with Dual mass Flywheel..

Terry of Terry's Transmissions told me the chatter I get from that sweet spot where there is no acceleration  OR deceleration load, can be eliminated with a dual-mass flywheel.. Says it keeps a "minor" load on it at all times = less/no free chatter...
Thoughts?

reamer wrote

Terry of Terry's Transmissions told me the chatter I get from that sweet spot where there is no acceleration  OR deceleration load, can be eliminated with a dual-mass flywheel.. Says it keeps a "minor" load on it at all times = less/no free chatter...
Thoughts?

It works for diesel Volkswagens. If you replace the factory dual mass flywheel with a single mass flywheel (a fairly common mod) one of the side-effects is transmission chatter.

Are there dual mass flywheels for gas applications? I thought only diesels got them 🤷‍♂️

Dual mass / DMF is a dirty word in diesel circles because they like to grenade and shatter the ZF main case, not to mention the clutch & flywheel set being $600-$800 price range to replace. The adage is that it does not hurt anything except your ears so most people try different fluids, add sound deadening material under the carpet, turn up the radio and live with it. Honestly if diesels didn’t need overdrive so bad I’d be tempted to keep my T19.

Like I said in the other thread 'its a truck transmission in a pickup truck. if you want a car go drive a car'

Or do like I do and keep your foot in it until you run out of steam or room to accelerate.
I doubt your Windsor's going to top out at 130, but I don't know your gear and tire size.

No DMF for 460's, I doubt the little Windsors got one.
https://www.zf.com/products/en/buses/products_29241.html

Edit: perhaps you ought to check the backlash in your R&P.
While the DMF was installed on diesels to smooth out torquey power pulses from the engine, you're not getting that while cruising in 5th with a 351.

Throw it in neutral and see if it's just rollover.
If it is, overfill through the shifter tower or run a thicker one of the MANY Zf approved lubricants and expect sluggish shifting when cold.

Have you considered the Mazda 5-speed?

It's a lot more like a car gearbox, and your having a 150 there's no real downside.

ArdWrknTrk wrote

Have you considered the Mazda 5-speed?

It's a lot more like a car gearbox, and your having a 150 there's no real downside.

I have the Mazda 5-speed in my truck and I'm quite happy with it...BUT, it does get a fair amount of hate from a lot of the truck crowd. I even have a spare 88-91 M5OD spare trans for rebuilding (winter project one day perhaps). I think Ron uses his truck for towing a trailer sometimes, so he probably wants the heavier trans...just guessing.

Fair enough.
I've not heard him mention pulling a camper, boat or equipment trailer.
Maybe I was not paying attention.  

Again... it's an old (tech) truck.
If you want it to do truck things, get used to it.

Or drop the better part of $100,000 like Gary did on Blue.

Yeah, it has to work sometimes, other times, truck shows. I like the ZF,,,Beats the no-OD NP435 with granny 1st.

Nice! Like a real cowboy wearing a Stetson!

Do like I said and throw it in neutral while coasting at highway speed.

You'll know right away if it is rollover rattle or coming from the rear (or maybe even the transfer case)

At any rate, you'll have a much better understanding of the noise that bothers you so much.

Thanks Jim
Actually the T-case is at Terry's right now being inspected, re-sealed.. Most of the leaks in the drivetrain is from the T-case.

May do what you suggested and go with a heavier fluid, since it's not a winter driver. any suggestions on fluid?

I don't have the link anymore since ZF changed their website.
If you find the zf5 s42 troubleshooting manual on their site they have a huge range of fluids.

Everything from light mineral oils and ATF up through full body gear oil.

Will do!

We have several ZF manuals on the site: Driveline/Transmissions/Manual Transmissions/ZF5.  Might that info be in there?

Ron,
That list of 01/19 is certainly much more current that the list I had bookmarked.  

Obviously Mercon V  is the current Ford fill.
Iirc my fill plug was tagged 'type H'

But as a summertime driver SAE 75-80 shouldn't drag the synchro's too badly.

When I had my ZF, 1988 F250, 7.3, I tried a few fluids. Amsoil ATF worked the best. Good shifting hot and cold.

I’m not an Amsoil dealer or big fan, but I have had good success with their ATF. Really helped our Suburban, it would “hunt” between lock up and third and OD.

Dane, I would say the same about Royal Purple Synchromax.

When I first got my Zf-5 it had been sitting outside for years.
Because I had a crisis when I blew the input off my T-19 it went into service without opening it up.

I drained and filled what I can only call 'strawberry milkshake' a few times and ordered the RP from Amazon.
I will say it shifted better with the $$ gear oil, but I can't say if it was any quieter.
I know my gearbox is old and tired.
It has the common rattle at idle in neutral and the pocket bearing if I lug it when hot.

Anyway, like you I'm not shilling, just a satisfied customer.