Engine/Transmission (1998.5 - 2002) Stock Clutch Holding Capacity

[Rebel_Horseman]

This may have been covered at one time before. If this is redundant then I apologize.



What is the holding capacity for the stock clutch? I'm looking to do some power mods in the near future, but I don't want the clutch to crap out. I just purchased my truck and it has 145k on it. I believe this is not the original clutch and has been rebuilt but I could be wrong. I will likely do a small bomb first such as 275's or DD1's and then add a box later on. Can I add injectors without putting a lot of additional wear and stress on the clutch? Any thoughts?



Brian [><]

 

[Ross]

stock clutch limits

You should be able to add either the 275's or the DD-1s without any problem. Add a computer that adds lots of fuel (TST, Blue Box) on top of that and you may have probs. My stock clutch didnt' give up til I added DD-IIs Van Aaken, and TST piggy-backed. Then, the tires would slip in 2nd and 3rd, and the clutch would slip in 4th and 5th.



Of course, this only occurred when "playing". When towing, the injectors are all you need.



By the way, avoid the 275's (been there), go for the DD-IIs.

 

[plongson]

First look at my sig. I still have the stock clutch. This is my experience pulling my rig (17,000 GCVW) up a steep grade.



I can only slip the clutch when the Ambient is low (<80°) and the elevation is low (<3500').



When the ambient temps are high (>90°) and the altitude is high (>4000') the EGT gets to 1150° to 1200° VERY fast and I back off or down shift.

 

[24Vpirate]

with the dd2s no problem when i added the comp box without tapping the wire it will slip the clutch at will through 4-5-6. waiting for my SBC to show up so i can tap that wire

 

[TIngram]

mine did not slip with just the 275sbut the comp on level 3 will frie it in 3-6 thats with a real heavy foot. if you just ease around (why would you) then you will survive. my ofe is on the way tonight as we speek this will solve my problem. they say on average the stock will hold to 300Hp. i would say thats pretty accurate.

 

[Mad Bomber]

Stock clutch

Your stock clutch holding capacity also depends on how hot your injection pump is out of the box. There can be 40+- HP differance. A good example is my stock 01 ETH put down a 244 though the wheels:--) . Then you add a box or injectors and you be slippin it good. One way to help you is keep your RPM's up don't lug it in a high gear.

 

[CrewCabDiesel]

1st. Check with Peter at South Bend Clutch.

With my stock clutch and no bombs(when I first got the truck) clutch appeared not to slip with my 5th wheel but fuel mileage was terrible around 10 to 11MPG. I installed a new SBC OFE Clutch before bombing and noticed that the mileage went up to almost 13MPG for the round same trip. When I installed South Bend's 13"OFE I noticed that the old OEM clutch looked almost new and had lots of material on it yet. This tends to make me think that the clutch in the 5 speed is very weak and does slip a little when towing with a stock Cummins. But hey thats my 2 cents worth.

Kyle

 

[RustyJC]

Refer to my signature to see my truck's configuration. I was fine until I added the DD2's to the EZ - that's when the South Bend Con OFE went in! :{



Rusty

 

[mgoncalves]

Knocking on wood while I'm typing this,



My stock clutch is still holding fine. I could smell it once after abusing it pretty hard, but other than that no problems.





Matt

 

[C. Harlan]

saw one the other day hold around 380 HP... . pretty impressive for a stock clutch! it was on an ETH/DEE setup though... I am sure those are a little more stout.



-Chris-

 

[Hohn]

I haven't dynoed, but I have had NO slippage with DD2 and an EZ, even when towing WOT uphill with 6K out back. I am probably near ~350ish rwhp.



Stock clutch capacity varies wildly. Some don't even make it to 300rwhp. Some hold 350+. It's a crap shoot.



If you want to push the limits of the stock clutch, I would suggest you favor injectors over a box for power. If you DO get a killer box, then I suggest you keep the levels down low and let the injectors do the work.



The sudden 'hit' of power from a box will often cause the clutch to slip earlier than if you just had the smooth power delivery of the injectors alone.



Justin

 

[RustyJC]

Building on Justin's point, we tow a 13,500 lb 5th wheel that puts us on the road at 21,180 GCW (21,500 GCWR). After installing the DD2's, I unplugged the EZ's data link cable and left the MAP cables plugged in so the EZ was just acting as a boost fooler. The stock clutch never came close to slipping. The power characteristics were very much like the "soft" settings of the stock truck, just with more torque across the RPM range.



With the EZ plugged in and the DD2's, however, I could slip the stock clutch running empty just by nailing the throttle at 1900 RPM in 5th or 6th gear. :{ When the power comes on immediately and hard, the stock clutch would "ratchet" as soon as the boost hit.



Rusty