99 w/ factory 6speed and 1-1/4" input shaft.. what size clutch?

[AndyMan]

Looking for a new clutch. I don't want to talk about SBC, vs. Valair, vs. Zoom, etc... I just want to understand what EXACTLY is between my transmission and my crank.



I'm thoroughly confused. I don't feel that anyone really acknoledges the factory "hybrid" set up in the early 6 speeds.



I've put the stuff below in QUOTE tags just to make it more readable... I'm not referencing other posts.

Here's what I "know":



1. I have a 1-1/4" input shaft.



2. 5 and 6 speed use the same pilot and release bearing config and part numbers (aftermarket).



3. Big difference in F/W’s, both use same crank bolt pattern, but the bolt patterns for their respective covers are different.

13. 578” for the 5 speed

14. 125” for the 6 speed.



4. Crank to friction is the dimension from the cranks mounting surface to the clutch mounting surface.

5 and 6 speed, 1. 508”.



5. Crank to ring gear, nearest face to crank.

5 speed, . 662”

6 speed, . 088”

Here is some of what I have "HEARD":



1. early NV5600 had a 12 spline 1-1/4" input, 5 speed has a 10 spine 1-1/4" input.



2. Have an early 5600 in my 98. 5. It bolted right in, no clutch change

Biggest issue is ring gear position relative to the starter. We know that a 6 speed system fits in a 5 speed bellhousing. If I jump out and buy a clutch for a 6 speed, and it's set up for a 5 speed ring gear then my starter won't engage properly. Vice-Versa for the 6 speed.



Does anyone KNOW what size flywheel was in the early 5600's? How about the num of splines on the input shaft? etc... etc...



Any help here would be very helpful.



Thanks,

Andy

 

[n7gxz]

I know that the 6-speeds with the 1-3/8" use a spacer between the starting and the flywheel housing/adaptor to move the starter gear back. The ring gear on the flywheel is on the edge closest to the engine and not centered on the flywheel.



Kevin

 

[pwerwagn]

This is the way I see it:

If you have an early 6-speed in place of the 5-speed, and it bolted in with no clutch change, then the spline count and shaft diameter have to be the same, otherwise the input shaft would not have splined into the clutch at all.



I have a 6-speed clutch on my 5-speed. What I did was have the factory 5-speed flywheel re-drilled for the 6-speed bolt pattern diameter. The bolt holes end up slightly to the inside the ring gear, barely missed. This way, I can still use the stock starter, in stock location, etc etc.



If your 99 was a factory 6-speed truck, does it have a 13" clutch or the 12. 4" clutch? If it has the 13" clutch already, then all you would need to do is get a 6-speed clutch from southbend or luk or someone, that is splined for the 5-speed (1-1/4").

If your clutch is the smaller 12. 4" setup that is the same as a 5-speed, I would presume that a 5-speed clutch (Con-O, whatever) would fit directly in place. If you wanted to up grade to the 6-speed diameter, you could jsut buy the kit to convert a 5-speed to a 13" clutch, or do as I did and re-drill the FW.



--Jeff

 

[pwerwagn]

from southbend:

We have taken the 13" ETH clutch and modified it to accept the 1 1/4" input shaft. By doing this, it enabled us to offer a disk center that is 2-3 times larger and stronger then can be provided in the 12 1/4" clutch kits. This kit comes with a flywheel, re-drilled and refaced to accept the larger clutch and is rated to handle up to 450 horsepower & 1000 ft. lbs. of torque. Years 1989-2003 5 speed & 6 speed non-ETH.

Since it says 6 speed non-eth, I assume it will work fine for you.



--Jeff

 

[South Bend Clutch]

As pwerwagn said, from 99-2000. 5 (July 5th) Dodge offered a six speed with the 235 HP. This supports the 1 1/4" input shaft and the 12 1/4" clutch with the 5sp ringgear location. When they went to the 245 HP HO engine, the clutch was changed to the 13", the input shaft was changed to the 1 3/8" and the ringgear was moved back towards the crank . 500". So they made an aluminum spacer to back the starter up . 500". In 2003 when they went to the common rail, they did away with the aluminum spacer and built it in.



Peter

 

[AndyMan]

Very interesting. Thanks to all for the input.



I figured when I started this thread that the hearsay would come'a flying. It seems that up until now that's all I have been able to find.



Thanks for the information all.



Andy