What year did G56 get introduced

[AH64ID]

1st has never been too high, but I sure would like 6th to be at 2000 rpms around 60 vs 67.

 

[Grizzly]

I sure would like the . 79OD that it had from 05. 5-07. 4 thou.

Do you feel that's better than . 73 on the NV5600?

 

[NIsaacs]

1st has never been too high, but I sure would like 6th to be at 2000 rpms around 60 vs 67.

Thats too slow when you are empty, you need a 7spd:-laf



Nick

 

[RVTRKN]

Unless you have the proper resurfacing equipment, the NV5600 flywheel will be ruined if you try to resurface it. They have a taper to them and resurfacing will flatten it out, and can cause major clutch issues. When clutch replacement is necessary, replace the flywheel, unless you know of a shop that can properly resurface it, but I doubt that.

 

[GCroyle]

Unless you have the proper resurfacing equipment, the NV5600 flywheel will be ruined if you try to resurface it. They have a taper to them and resurfacing will flatten it out, and can cause major clutch issues. When clutch replacement is necessary, replace the flywheel, unless you know of a shop that can properly resurface it, but I doubt that.

RVTRKN,



The Dodge FSM does in fact have information that describes the exact concave (by a few thous. ) surface you are reffering to. But I think we need to introduce one qualifier. The FSM statement covers all engines used in the Ram, gas 6 and 8 cyl and the Cummins. The Cummins F/W was supplied by Cummins, look at the casting numbers. The gas versions, Dodge production. I think if you had the gas versions and Cummins all new, all side by side and used at least a machinists straight edge you'd find the concave on the gassers but the Cummins version is flat.



One of the clutch mfgr's actually printed a bulletin years ago describing the WHY behind the concave castings. At first it don't make sense but it actually can help because if the castings are slightly concave the contact to the disc starts at the friction material OD, starts the disc rotating and then as it continues the clamping process compressing the lining springs you wind up with a fully clamped disc that saw very little RPM differential when the ID finally clamped. This often looks like the ID wasn't making as much of a contribution to the clutch as it shows less heat marks or apparent wear. The other benifit is that as the castings get real hot and try to expand its claimed that the casting goes flat from heat and still operates well. The BIG thing to inspect a reground F/W for is never accept a convex (center higher ) surfaced F/W this is a reciepe for a slipper. The other concern is deeply imbedded hot spots. The surface looks good, but the hot spot became Martensite and that is some bad stuff. Harder and actually expands upon higher heating and forms high spots. Major contributor to chatter after several months of no chatter service then it shows up. Bad stuff.



This GM F/W has been resurfaced and you can see the shadows of the hard hot spots clearly in this pic. If you're bored sometime and have an old F/W with hot spots try drilling into the cold outer area, no problem, now CAREFULLY using the same drill, try drilling into the hard hot spot. Be carefull and be prepared to fail if you truly hit the hot spot.



Gary



We had a lot of help with the Martensite from one of our sister compaines, Webb Wheel and their casting guru.

 

[AH64ID]

Do you feel that's better than . 73 on the NV5600?

Absoloutly. The increase in rpms and rear wheel torque for a given speed is huge when towing in the mountains. My dad is able to pull more weight with less power in 6th on his 06, simply due to the . 79 ratio.

Thats too slow when you are empty, you need a 7spd:-laf

Nick

Tell me about it! I would like to see a . 82:1 6th and a . 7:1 7th.

That's why the G56 was changed from . 79 to . 74, it improved empty driving and hurt towing performance (at least in mountain states).

 

[Regcabguy]

Carrying weight all the time enables the 0. 79 to work well for me. Much easier on the driveline even w/34" tires. There's got to be an engineering reason why the NV5600 and the G-56 don't come with granny reverse. If I ever chuck the camper,I'll probably go to a 285-75-18.

 

[Joseph Donnelly]

The 68RFE has . 82, . 63 fifth and sixth; the Aisin has . 77, . 63.

 

[RVTRKN]

GCroyle, I've never checked any flywheel for a taper, in the old days when I did my own clutch jobs, it was standard for me to take the flywheel in for resurfacing if there were no hot spots. When I first bought my 04. 5 with the NV5600, I had a discussion with my trany tech at my Dealer, when he stated that the flywheel has a taper and not to resurface it, for it will ruin it and cause clutch problems.