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G56 clutch options

4K views 16 replies 11 participants last post by  Danderson 
#1 ·
Hi all, I recently purchased a 2010 with a 6.7 and the g56 and doing the Deletes and the Milage tune, the truck slips the clutch pretty easily. I'd like to avoid swapping from the DMF but it's not looking like there are any options that will hold up to the new power the truck makes.

if there is any one near Portland Oregon that has done the swap to a SMF I'd like to hear what the gear roll over sounds like, the clutch tension etc. I gotta make sure the wife can still drive it for our long trips.

Probably won't tow much more than 10k on a semi regular basis and its daily driven
 
#2 ·
well if you do make the choice to swap I would go with a southbend. either a single disk or a dual disk. I have the dual disk and I can say that the tension in the pedal is night and day difference from the stock but it was ok enough for my gf to drive. so it shouldn't be to bad for your wife. it is a whole lot more grabby and is designed to handle the torque and HP of the deletes. if you put one of those in you will probably never have to worry about another clutch.....at least not until 500k miles.
 
#3 ·
i did a single disc DMF in my old truck (07). gear rollover was there but greatly reduced once I switched to mobile 50w tranny fluid, it was a little jumpy, but that's clutch selection. it growled below 1000rpm but I loved it, you won't be disappointed as long as you get the 50w tranny fluid
 
#5 ·
Awesome! I was concerned when South bend stated the gear rollover was bad when you were in the lower RPM as my normal driving range is between 1k-1700 RPM but it's probably gonna sound similar to my SM456 I had in my old chev which I can totally live with. I just didn't want it sounding like it was about to take a dump
 
#14 ·
I don't notice any gear noise in mine at those rpm's. I'm in low gears at those rpm's alot. Had an older f250 once that had the NP435, extremely similar to the SM456. It moaned at low rpm's, night and day difference between those and the G56.
 
#7 ·
mine sounds like a wrench in a coffee can when I am below 1500 rpms. I will keep it in a lower gear to keep it just over so that it doesn't rattle to much. the ability of the clutch to hold all the power and not slip is where I revert back to when I start to get annoyed with the sound so I don't go bonkers with my $60k trip rattling like that. its a little loud but it's so worth it.
 
#8 ·
That seems to be the key. The less you lug them around the less noise you have. The heavier oil and adding an extra quart really seems to help also. I notice on my sb dd that when in neutral it can be noisey at times but push the clutch in and let it out slowly and the sound goes away.
 
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#9 ·
I ran a SB DD3250 in my 08 G56 deleted and tuned. I wouldn't go any other way, it was a great clutch. I swapped in some lube that was for the Mercedes transmission, I believe it was 50w. It helped the shift feel and quieted it down a little.

The key with the SMF, as already stated, is to not lug the engine. Shift around 2k+ and it helps the noise a lot.

Other than thinking about shifts a little more the clutch was awesome, held up to heavy towing (27k+ GVW) and normal driving.

Good luck getting squared away, the stock DMF and clutch aren't rated for your increase in torque as you've discovered. Mine slipped immediately upon deleting and tuning just like yours.
 
#10 ·
I've got the SBC OKHD single. Silent in operation but gear rollover is inevitable. I use Amsoil 75-90 MTG. As stated bogging the trans or putting through the 'hood induces some growl. Extending those shifts is imperative.
My clutch held Smarty on sw#7 in 5th. Currently it's holding Anarchy EFI on #3 and #5 if I cool it on the pedal.
34" tires and a constant load of 1800#.
 
#12 ·
I have the valair quiet organic and it is even a little rough backing up a trailer. Especially little short trailers that are very sensitive to steering input. Mine hops every night when I back my trailer in the drive. Just part of the sacrifice to adding more power I suppose.
 
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#17 ·
Yep,especially with your higher geared final drive G-56.
My year had the 0.74 final drive which yields super high rpm's with stock tires.
I had a leaking rear main and converted to an SBC OKHD.
However,my stock dmf looked fine after 37K,34" tires and an 1800# popup. In addition it held a Smarty sw#3 and #5 default for all that time.
 
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