06 5.9L G56, Bad vibration @ 2700RPM

[ManiacMike]

I have the sb dual disc (street). I switched to delvac 50 when it was installed so I can't comment on noise with other oils. For me it is only slightly noisier than a sb single disc except in 5th below 1600 rpm. Anything more than very slight throttle and the transmission rattles like a bunch of marbles. Hit 1600 rpm and it goes away. All other gears are quiet. In neutral you can hear the clutch rattle a bit but it isn't bad.

Changed over last night to the Mobil Delvac STF 50, un mixed in TC, mixed with RP Syncromax and the truck is almost back to pre-clutch noise levels. I like it.....a lot

 

[RVTRKN]

The NV5600 will eat sixth if you tow heavy in sixth. But the temps will be different the G56.

 

[DClark]

G56 transmission oil

i have never heard of getting that many miles out of a dual mass flywheel, you may have just set a record. southbend makes a kit that includes everything. a single disk conofe kit will work for you. while the g56 is out fill the g56 with sae 50 wt synthetic syncromesh transmission fluid then pour two or three quarts of royal purple syncromax in the top and replace the red rubber boot with a dorman 614-002. the dmf has a bad habit of damaging the input seal, change both the input seal and bearing. here is a list of some of the 50wt oils. delvac from ww granger is in gallons the other in 5 gallon pale only. if 4wd replace the transfer case to the 50 wt. i just seen the amsoil dealer, the amsoil part is at the bottom the royal purple syncromax equal is amsoil manual transmission fluid, it used to have 5w-30 on it but the new box i did not see it.
Delo Synthetic Transmission Fluid SAE 50
Delo Synthetic Transmission Fluid SAE 50 delivers exceptional all-climate, year-round performance in heavy duty truck transmissions. A unique additive package can protect gears without using the “active sulfur” agents commonly found in automotive axle oils. This results in little to no corrosion and long life for copper-containing parts, such as oil coolers, bushings, and thrust washers. Good pumpability in extreme hot or cold temperatures promotes smooth shifting and efficient power transfer. It is specifically formulated to meet the latest extended drain requirements for Eaton transmissions, with drain intervals of up to 500,000 miles.
Synchromax is recommended for manual transmissions
that specify an automatic transmission fluid or motor oil.
It is also ideal for transfer cases and 2-cycle motorcycle
gear boxes.
Synchromax is formulated with Royal Purple’s synthetic,
proprietary Synerlec additive technology, offering
improved shift quality over a wide temperature range and
reduced gear noise.
Synchromax is fully compatible with all types of friction
materials and offers excellent corrosion and oxidation
protection without affecting the soft metals commonly
found in manual transmission synchronizers.
Performance Advantages
• Greater wear protection
• Smoother shifts
• Excellent rust / corrosion protection
• Reduces friction for more power
• Lowers operating temperatures





Delvac from ww granger
Castrol 50 wt is syngear CD50 o’rileys p/n syn 50-5
Amsoil FT F05-EA

I have a G56 in my '05 and currently use Penzoil syncromesh I believe its called. I want to be sure that I understand what you are specifing here. Fill with 5 qt(I believe that is the spec for the G56) 50 wt (Delo, Delvac, Castrol or Amsoil, my choice then add 2-3 qt Royal Purple to that. Is that correct? I'm not sure what you ment by the 50-50 or 70-30. What two oils would make up that blend? Sorry for the late read on this post.
DClark

 

[MEGATRK]

I have the sb dual disc (street). I switched to delvac 50 when it was installed so I can't comment on noise with other oils. For me it is only slightly noisier than a sb single disc except in 5th below 1600 rpm. Anything more than very slight throttle and the transmission rattles like a bunch of marbles. Hit 1600 rpm and it goes away. All other gears are quiet. In neutral you can hear the clutch rattle a bit but it isn't bad.

I have been looking at the SB G56-OH-DK (single disc) and now looking at the Street Dual Disc. I hear the Dual can be noisier, but how much. Will I even hear it over my exhaust? 5" turbo back straight pipe. Have to keep the wife happy, as this is my daily driver as well as our road trip vehicle? I'm planning on getting a Smarty in the future. The single disc is good for 425HP and the street dual is good for 650HP. The single is quicker shifting than the dual, so I've been told by someone from SB. I went through the list of vendors/installers off of SB's list and most of them are out of business. I did find someone local from a co-workers recommendation to do the install for $650. Now to decide the single disc of the street dual...

 

[MEGATRK]

Thank you everyone for all of the information. I greatly appreciate it.

 

[Regcabguy]

The NV5600 will eat sixth if you tow heavy in sixth. But the temps will be different the G56.

We have Summit Transmissions here now,an SBC authorized installer.
Mechanically Inclined Technicians does clutches also here.

 

[RVTRKN]

I have been looking at the SB G56-OH-DK (single disc) and now looking at the Street Dual Disc. I hear the Dual can be noisier, but how much. Will I even hear it over my exhaust? 5" turbo back straight pipe. Have to keep the wife happy, as this is my daily driver as well as our road trip vehicle? I'm planning on getting a Smarty in the future. The single disc is good for 425HP and the street dual is good for 650HP. The single is quicker shifting than the dual, so I've been told by someone from SB. I went through the list of vendors/installers off of SB's list and most of them are out of business. I did find someone local from a co-workers recommendation to do the install for $650. Now to decide the single disc of the street dual...

If your stock or a little over the stock HP, I personally would go with the single disk. I've never had mine next to a SD clutch to compare, but as noisy as my SBC DD 3250 is vrs what the reports are here on TDR and other sites for the SD, I would chose the SD. Unfortunately mine requires better holding capability than a stock setup even though mine is completely stock except for the SBC SMF with the DD 3250. My truck had an update to the ECM in 09 that now has a surging issue when in regen, and that took out the stock clutch, so my truck requires the DD clutch.

 

[RVTRKN]

I have a G56 in my '05 and currently use Penzoil syncromesh I believe its called. I want to be sure that I understand what you are specifing here. Fill with 5 qt(I believe that is the spec for the G56) 50 wt (Delo, Delvac, Castrol or Amsoil, my choice then add 2-3 qt Royal Purple to that. Is that correct? I'm not sure what you ment by the 50-50 or 70-30. What two oils would make up that blend? Sorry for the late read on this post.
DClark

50/50 for mine is Mobil Delvac http://www.mobil.us/usa-english-lcw...l-delvac-synthetic-transmission-fluid-50.aspx and Royal purple synchromesh, that CKelley1 recommended so it would be 70% Mobil & 30% Royal Purple. In a couple of months I'm updating my oil to reflect the transmission cooler I'll be installing and will go with strait Royal Purple or Pennzoil Syncromesh.

 

[Regcabguy]

I ran Pennsoil Synchromesh prior to CKelley's recommendation. Shifts easier but has way less sound reduction qualities. I actually had people staring at the truck in parking lots with the clutch out in neutral.

 

[RVTRKN]

As long as it runs cool, I'll be happy, but I may run strait 50. It all depends on the ability to cool the oil easier.