G56 with strange noise (SMF)

[SquareDave]

At 195K replaced DMF with SMF conversion kit (Valeo) after throw-out bearing failed in 2006 Ram. The noise isn't bad below 60 mph. However, an audible tuning fork sound begins at 60 and reaches its peak at 65 and starts to fade at 70 mph. Much of the time I can reduce or even eliminate the tone just by putting my hand on the shifter. The transmission is filled with 8 quarts Mobil Delvac.

Pilot bearing was toast at 270K so the shop recommended a LuK kit since it was already apart. The clutch is much smoother now, and shifting gears is easier, but tuning fork noise is still there 60-70 mph. It may be that the various vibrations in the transmission converge at a tuning fork type frequency at certain speeds, but that's just my guess.

Has anyone out there run across this?

 

[cerberusiam]

Stock or tuned? Tuning and timing advance make a HUGE difference in trans noise in the harmonics range. What rpms does it occur?

 

[SquareDave]

Stock or tuned? Tuning and timing advance make a HUGE difference in trans noise in the harmonics range. What rpms does it occur?

Stock except for SMF conversion kit. No tuning.
6th gear: +/-2100 rpm 65 mph | 5th gear: +/- 2300 rpm 65 mph | 1st - 4th gears: no issues up to +/- 2300 rpm
I could tap out Morse code on the gearshift knob with one finger (if I knew Morse code).

 

[SquareDave]

Stock except for SMF conversion kit. No tuning.
6th gear: +/-2100 rpm 65 mph | 5th gear: +/- 2300 rpm 65 mph | 1st - 4th gears: no issues up to +/- 2300 rpm
I could tap out Morse code on the gearshift knob with one finger (if I knew Morse code).

Make that 5th gear rpm 2900. Ring finger went south on 10-key instead of north.

 

[cerberusiam]

Probably the 5\6 slider gear them. Those are th emain 2 gears that take all the abuse.

 

[SquareDave]

Probably the 5\6 slider gear them. Those are th emain 2 gears that take all the abuse.

Makes sense. I have to wonder it that could have been the source of early pilot bearing failure (TOTAL failure - not one needle left). In over 50 years driving I've never ever worn out a pilot bearing. Drove Toyota 140,000 miles and 2004 Dodge 180,000 miles with no issues. Took 2006 Dodge to 195K until t.o. bearing failure.

Will have an expert take a look at it later this week.

Thanks for your input.