Engine/Transmission (1998.5 - 2002) Stiff Shifting Six Speed

[RustyJC]

OK, I'm Worried Now!

My SBC Con OFE is being installed as I type this. This clutch was recommended to me not just because of my truck's current BHP rating, but also because our truck is used almost exclusively to tow our 13,500 lb 36' 5th wheel. When we hit the road, we're at 21,180 lbs GCW (21,500 GCWR).



With all the comments regarding the OFE chattering, not allowing the trans to go into gear, etc. , I'm frankly wondering if I'm doing the right thing here or not! What good is the truck if I can't even start on an incline while towing or back the 5ver into an uphill campsite, let alone get it in gear to begin with?



Rusty

 

[Hohn]

Rusty, don't be worried! The OFE is the right choice for you. But one thing about the SBC clutches-- they have to be installed and broken in a certain way.



For one thing, make sure that whoever is dong the installation resurfaces the flywheel properly. Per Peter @ SBC, this is critical, and must be done on a machine specifically designed for flywheel resurfacing.



As for break-in, I would contact Peter as to what he recommends other than waiting 1K miles before towing. I would imagine that slipping it a little and doing second gear starts would probably help mate the clutch surfaces to the flywheel.



Justin

 

[tpruitt]

Rusty i did not mean to worry you. i think that you got the right Clutch. The SBC are great clutches. You will have to give the clutch some time to set in. It took about a month for my to set. It will slip in the beginning but after that it will hold real good.



As to my earlier post. Mine was an overnight issue, and like i said earlier it does not happen all the time. The Night when I started to have problems i had the box on 5x5 and i got into it pretty hard. when i got out of the truck i could smell where the clutch had slipped. Maybe when it slipped it broke something like a spring. I don't know what OFE you got but i have the one with the upgraded material on it and that could be causing it to bite harder on take off. I have not had anymore problems with the clutch slipping.



I will keep everyone updated on my situation and how well the MTL works.



Thanks,

Trey

 

[Rman]

Hey guys, one thing i have noticed about my particular 6 speed. WHen i'm stopped at a light, i leave the clutch out leave it in nuetral. When i have to go i depress the clutch and dive into second, well occasionally it won't go, unless i use force.



Well force is bad, so i pull slightly, then relax, then go back to it and it almost always slips right in without hesitation. It's almost like setting the synchro's then going in. Just something i've come across, i do use RP synchromax and have had no ill effects. I do want to use MTL just to see, but i think i wait another 15k first. I changed over to RP at about 10k. I'm at about 24k right now.

 

[tpruitt]

rhickman it sounds like you are having the same problem that i am. I will let you know how the RED LINE does

 

[T Peterson]

same problem

I've had the same problem for most of the last 40,000mi. Dealer dropped transmission @ about 20k and found a thick grease like substance on the input shaft, they cleaned it up, replaced throwout bearing and supposedly the pilot bearing. I saw the clutch and pressure plate and flywheel and they all "looked" good. They put it back together and it worked great for about 4000mi. it got progressively worse, so I tried the Redline MTL, drove it for about 1000mi. , shifting was more notchy so I switched back to stock fluid, personally I like the stock stuff better, but I also believe my problem is the clutch, not the transmission, it just hangs up and drags, I'm just waiting until I can afford a SBC



Tom

 

[South Bend Clutch]

Guy's,



Ever sense this stiff shifting problem started whether it be our clutch or someone else's or even the ones coming new from the dealer we have been busting our butts to find an answer. Although in some cases it is the transmissions and a lube change may help, we felt there had to be something else. Now, from all the descriptions of how the clutch operates (where it engages) it could not be clutch related, On our behalf, we put every clutch through an intensive process on very expensive machinery to ensure the clutch system is operating properly. We know the clutch is releasing with a maximum of . 600" travel and the hydraulics offer at least 7/8" travel. Now, what does that leave us? If the input shaft is still ever so slightly turning and the clutch is released. 1st and reverse are mainly the problem and sometimes 2nd and all that needs to be done is to slide the shifter up to 3rd or 4th to stop the input shaft from turning so you can go back to 1st or reverse then it has to be the pilot brg. So we directed our attention to the pilot brg. We always use the latest OEM pilot bearings that are available so we started doing some comparisons. We found a box of some old ones that we had purchased some time ago and compared them to the ones that we are getting now and OH MY GOD!!!



The original equipment manufacture made some changes to the two seals at either end of the brg. . They looked bigger then the earlier ones. So we grabbed a new input shaft and tried to slide the pilot brg. on to the shaft. Guess what we found? We could barely get the latest design on, way to tight. We believe they made the change when they made the ETH HO trucks. So we got a guy that was having this issue and had him bring his truck to our shop. This was a factory clutch, nothing had been changed inside the bell-housing from new. Pulled it apart and all we did was change the pilot to the older design and reinstalled the transmission. The problem was fixed, it just fell into all gears with ease.



So now we took the new pilots and ground the seals down a little and tried them again on a new input shaft and they went right on with ease. The problem is the pilot brg. seals are to big and are gripping the end of the input shaft to tight causing the input to continue to turn when the clutch is released. Change or fix the pilot brg. and fix the problem.



Peter

 

[T Peterson]

Thank you Peter! I'll be calling you.



Tom

 

[RustyJC]

Peter,



Based on the above, what pilot bearing was included in the Con OFE Andy shipped for my 2002 Cummins HO/6 speed a couple of weeks ago? My clutch installation should finish up today - I'd sure feel better knowing the right pilot bearing has been installed.



Rusty

 

[Hohn]

Wow! This is awesome to be learning this straight from the man himself.



These are the kinds of things I had in mind when I decided to get an '02. I figured that they would have all the kinks in the system worked out by then, so I would be happier with my truck. So far, it has been wonderful.



Anyone know where we can get a diagram or sketch showing how the various clutch parts go together? I understand basically how the clutch works, and which parts do what, but I am not intimately knowledgeable as I would like to be.



Justin

 

[RustyJC]

Originally posted by Hohn

Anyone know where we can get a diagram or sketch showing how the various clutch parts go together? I understand basically how the clutch works, and which parts do what, but I am not intimately knowledgeable as I would like to be.

Justin,



How's this?



This doesn't show the pilot bearing/bushing. It's located in the rear of the crankshaft and supports the front of the transmission input shaft.



Rusty

 

[Rman]

Rusty, did your truck have any difficulty with the original clutch? I have an 02 with about 24k on it and it's not bad, but i do notice it. Just curious, let us know how it does with the SBC installed. I want to get one, but i think i'll get a little more use out of my stocker right now. Perhaps i'll take it down and change the pilot... seems like a lot of work though if i'm not getting a better clutch out of it!

 

[RustyJC]

Originally posted by rhickman

Rusty, did your truck have any difficulty with the original clutch?

Not a bit until the DD2's went in. My wife and I went on a test drive, and she nailed it at 1900 RPM in 6th gear (unloaded). I felt a ratcheting, juddering sensation and noticed the tach had jumped to 2300 RPM and was holding steady while the speedometer chased it. Oops! :{



Well, since we tow a 13,500 lb 5th wheel, I could see the handwriting on the wall, so the order went in to Andy for the Con OFE!



Rusty

 

[tpruitt]

New pilot bearing ordered and it will be here Monday and in the Trans by Monday Afternoon. Cant get better service than that. Oo.

 

[AC]

Peter, is the pilot bearing something that would have been replaced when my new clutch was installed? I don't remember having this problem before the clutch change.

When looking at the manual on removing and installing the pilot bearing the first thing they tell you is to remove the transmission and transfer case. Is there an easier way or is major surgery required? AC

 

[South Bend Clutch]

It is in the center of the flywheel which is bolted to the crank and requires the transmission to be backed out.



Peter

 

[Hohn]

Rusty:

Thanks for the link. I thought about that site just after I finished posting-- DUH.



Anyway, it makes me feel pretty lucky that my clutch is still doing so well. Granted, I only have 20K miles, but I was led to believe that EZ and DD2s would be certain slippage. It hasn't happened yet-- even WOT uphill in OD with 6K pounds behind me.



I noticed that when I tested the EZ on max aggression that the clutch seemed to be getting softer for sure. So I moved the jumper back to the tame setting, and all is well for now.



At first I thought that the high altitude was the reason my clutch was lasting (less power), but we have only been here in WY for about 3K miles-- the previous 5K before that were near Sea level in GA.



For now, I am trying to save the pennies to make enough power to properly break in a Con FE



Justin

 

[NVR FNSH]

Peter,

Do you have the specs for the input shaft OD and Pilot bearing ID on a '00 6spd (Non-HO)? I believe a large part of my shifting problem is the slave cylinder - I'm measuring 19mm of travel and the spec on Fritz's site says minimum of 24mm. The mechanic at the dealer measured 36mm somehow... . I'm going to replace the slave cylinder and if that doesn't solve my problem I'm going after the pilot bearing.



Brian

 

[South Bend Clutch]

The input shaft where the pilot rides is . 750" and the pilot should slide on with ease.



Peter

 

[csevers]

:--) So what you are saying is I took it in the butt to the tune of $925 because of a $10 bearing?? Glad you got that figured out.



Craig