Engine/Transmission (1998.5 - 2002) Hard Shifting

[John Berger]

I'm running Amsoil 2K 75W-90 with one fastcooler and the Geno's filter kit. I also had the SBC con OFE clutch installed in May of this year. It has somewhere in the vicinity of 8K miles on it. Sometimes I have a problem shifting into reverse when it's cold. Sometimes it shifts hard after towing when I'm trying to back my 5ver into it's nest and I have to pull forward then into reverse. It always goes in, but sometimes it's a fight. When I come to a stop, I have to "hunt" for second gear. I always get it smoothly when I try shifting to 2nd the second time. I've read a bunch of the posts on hard shifting. The shifting started to become a problem not long after I put the Series 2K lube in the transmission. I also had the clutch installed in this same general time frame. I've heard that the pilot bearing that comes with the SBC clutches are not as good as the OEM part, due to no rubber seal to hold the grease in. So is it the lube, the pilot bearing or the slave cylinder? I have heard of reports of harder shifting with the Series 2K lube. I did not have a shift problem with the factory stuff or the Amsoil 75W-90 GL4 lube. I also did not have a SBC clutch in when using those lubes, so I don't really have a good baseline to go with. Any suggestions would be appreciated. I don't want to wander from fix to fix, spending money like it's going out of style. My first inclination is to change the lube out and see what happens.

 

[John Berger]

I went to a GL4 lube and the thing still shifts hard. I did not see any brass or junk in the lube when I drained the transmission. The old filter looked used and nasty, but no noticeable metal parts. The bottom of the transmission felt clean and the gear teeth looked good. I took my slave cylinder off tonight to check the travel. The piston popped off, but I got it back on OK. The travel was fine. Sometimes this thing shifts fine, other times it doesn't. Other than hard shifting, what else would I want to look for if the problem is in the transmission? I might add that I'm not hearing any noises whatsoever while shifting. This is perplexing me. I think I'm going to order the NAPA slave cylinder and try it. I guess after that, I might have to take it in to the dealer and have them go into the transmission. Thanks for any help.



John

 

[redram]

If you're having problems shifting because the clutch is not disengaging, ie the reverse, try double clutching. If this improves the shifting, then it might be a weak slave or master cylinder. Otherwise, ?????



Good luck.

 

[Sageair]

My sons 97 started acting just like you described being especially hard to get into first and reverse. We simply made up a new rod for the slave cylinder which was about 3/8 of an inch longer than the original. We used 5/16 inch round stock available at hardare stores. It usually comes in a three foot length so you have plent to experiment with. We rounded the ends to look like the original using a bench grinder. The longer rod is still in after 15,000 miles and still works great. Might be worth a try. I found that I didn't like how little freeplay I had in the clutch of my 2001 so I made a slightly shorter than stock rod for mine ,works like a champ.

 

[South Bend Clutch]

Sageair,



If that worked for you it is hard to argue with, good job.





With the way hydraulics work, by lengthening the slave cylinder rod should only reset the starting point in the piston of the slave and should not have any bearing on the amount of travel that it produces. The reason for this is because the throw out bearing on the clutch fork always rides against the fingers of the pressure plate (only with hydraulic systems). By lengthening the slave rod should only push the fluid back into the master cylinder reservoir. The slave only does what it is told to do by the master cylinder. Theoretically if you extended or had a threaded master cylinder rod, then when you pushed on the pedal you would get more fluid movement thus telling the slave to extend further. If you were to do anything with the slave, changing it to a different diameter so you could get more fluid travel with the same amount of thrust offered by the master cylinder might help. Hydraulics is way different the the old linkage systems. With linkage style actuators there was a threaded rod down by the fork and if you lengthened the rod and/or took the free play out of the system (pedal) then you would be moving the bearing closer to the fingers (because it was not designed to run tight against the fingers) you would be creating more travel. Hydraulic systems do not have "free play"



I hope my babbling made sense.



Maybe I should forget clutches and work on a fale safe hydraulic system.



Peter

 

[John Berger]

I noticed two things while driving the truck this weekend. Every once in a while when I upshift from second to third, it comes out of second hard and into third hard. I noticed last night that sometimes when I come to a stop and I'm in second the truck continues to ease forward. I stop the truck with brakes and shift into neutral and let off the brake and the truck doesn't move. I tried this a couple of times and was able to recreate the movement. I had the clutch all the way to the floor. Most of my troubles come when I'm in stop and go traffic or backing up the 5'ver. The reverse to first or reverse to second seems to be the leading culprit. I'm awaiting an oil analysis on the transmission gear lube I just drained. Everything looked good, from the gears to the bottom of the transmission to the filter. No brass or shavings noticed. I'm hoping this is the slave cylinder. I have also tried pumping the clutch repeatedly when this problem occurs, but that has not worked. There are still no noises that I have noticed.

 

[Steve Campbell]

Just off the top of my head....

... I will get flamed for this... deep breath... The oil is too thick!!!



I only say this because of an old Chevy I was working on for a friend. He complained of the truck trying to move forward, in neutral, at start-up on cold mornings. We drained the "stuff" that was in the transmission out, put in the winter grade of recommended oil (can't remember what that was) and the problem went away.



Probably apples and oranges, but I thought I would increase my post count

 

[John Berger]

I got Amsoil 80W-90 synthetic in the transmission. I won't rule out lube, but I really don't think that's the problem. I've changed the lube in this transmission 5 times in 82K miles, the most recent being last week. I ran the factory stuff in it for over half of that mileage, the rest of the time it's been Amsoil. The reason it has been so frequent is because of BOMB's: Geno's filter kit and Verlyn's fast cooler. I think the most miles put on any gear lube was something like 28K. The transmission has been worked hard, but I don't abuse it and no lube ever went over 30K miles. In addition to the factory stuff, I've had Amsoil 75W-90 and the Series 2K 75W-90 in the transmission, in addition to the 80W-90 that I just put in. The temps have never run hotter than 210-215 degrees since I've been monitoring the transmission temps. That was towing the 5'ver up some real steep grades on a 90 plus degree day. By the way, the hard shifting did not start until after the con ofe was installed.

 

[emjay]

I've not worked on the Dodge manuals, but I do have a bit of experience with clutches. I am assuming that the clutch in question is the borg & beck style with three release levers in the hat (not a diaphragm clutch). Sounds to me like your clutch is dragging (not fully releasing). Since you tried pumping it up, it's probably not a hydraulic problem. Things I would look for are a bent release fork and/or cracked or fractured hat, either of which can happen with too much pedal travel, too long a throwout bearing, or incorrect release fork geometry/ratio.



Ideally, as the clutch is depressed, the release fork (if so equipped) should make full contact with the throwout bearing and clutch release fingers before the fork is perpendicular to the transmission shaft centerline, then continue to perpendicularity and past that point to reach full release. It should never push the clutch fingers all the way to their mechanical limit, otherwise the hat stretches and will eventually start cracking around the piovot anchors. Once that starts happening, the pressure exerted on the fingers further weakens the hat and your pedal travel is used up flexing the hat instead of releasing the clutch. I've experienced this firsthand, and had the same symptoms. Hope this helps... .



Good Luck, John.

 

[emjay]

I just looked at the South Bend Clutch Web site, looks like they're all diaphragm clutches. Oh well.

 

[KennyM]

John, I have the exact same issue. My transmission has always shifted very easy, had my SBC con OFE installed, drove for 1K to break-in. After towing my trailer for the first time with new clutch to Myrtle Beach, it started doing exactly what you stated.



If I come to a red light and knock it in neutral, then go to put in gear it will not go, I have to try about three or four time pushing real hard to get it in gear. Next time its smooth as silk?? As long as i'm rolling it seems to shift fine, only from a dead stop it seems to be hard. Also when it's hard to get into first , once rolling it sometimes wants to fight with getting it into second. Same for reverse.



Ken

 

[emjay]

FWIW, Hard shifting from a dead stop means that there is sufficient friction between the input shaft and the crankshaft to overcome the synchro friction, so either the synchro is too slippery (oil too thick possibly), the clutch is not fully released (becuse the disc is too "spongy" or insufficient pressure plate-to-flywheel gap), or the pilot bearing is seizing.



If changing oil seems to make no difference, and it doesn't get better when warmed up, it's probably not oil. If your clutch starts engagment with the pedal close to the floor, it's probably the clutch dragging.



The reason that it better when rolling is the closer the input shaft speed is to the crankshaft speed, the easier it is to shift because there's less momentum for the synchro to "dissipate".



If lengthening the pushrod from the slave solved the problem for Sageair, probably his release fork is bent.

 

[fj40charles]

The answer I got from Peter was it was caused by the slave cylinder. When you had the old clutch, the slave push rod was almost all the way out. The slave cylinder will have wear marks inside where the seal is. After you install a new clutch, the slave cylinder goes back in, but the the seals are now in a area that is already worn. This is much like some brake drum cylinders and why you should replace the drum when you put new pads on them. Hope this makes sense.



BTW, I'm having the exact problem you're having after installing my Con OFe clutch. I just don't want to spend 400. 00 for a new master and slave.



Leave it up to those idiots at DC to come with a **** poor design.



Charles

 

[John Berger]

Interesting and it's nice to know that others have experienced the same thing, despite it being a great big PITA. When I roll the truck to a stop and downshift into second just prior to stopping, the shifting is smooth as silk. By the way, I have never had a problem on a downshift, just upshifts. There is an aftermarket slave cylinder available from NAPA for anywhere from 75-79 bucks. Beats the hell out of the price DC charges. I thought SBC sold after market slave/master cylinders, and I read that on this board. Maybe they just provided one to a user.

 

[fj40charles]

I wish someone would come up with a decent aftermarket master and slave clutch cylinder. The slave should have a bleed screw.



I just can't see spending 400. 00 on the POS setup DC offers.



Charles

 

[emjay]

I still don't understand what slave cylinder bore wear has to do with what is apparently a diminshed slave stroke unless you're losing fluid or air is somehow sucked in through the compromised seal. Is that the supposition?



Also, wouldn't it be possible to drill and tap the slave for a bleed screw?

 

[Gary - K7GLD]

I think yer original suspicion about the pilot bearing, and/or sufficient misalignment of transmission-to-bellhousing is causing the transmission input shaft to bind and continue to rotate with the flywheel regardless of clutch engagement - making it APPEAR to perhaps be a clutch or lube problem, when it really isn't...

 

[M Barnett]

Years ago when my truck was stock, my hydraulics went out and I had the same problem, hard to shift. Had to put in a new one and no problems since.

Michael

 

[emjay]

If there's a problem with the master and the fluid leaks past the internal seal and simply returns to the reservoir, then yes, that is a possible cause. If that is not the case and you're not leaking fluid and there's no air in the system, the problem must be mechanical, i. e. bent fork, binding pilot bearing, etc. . Unless of course I've left something else out... ... . please feel free to let me know



P. S. Gary - I couldn't agree more... .

 

[BIG BOB]

Hey Guys! Don't throw your money away on DC with their replacement $400 Clutch Master Cylinder and Slave Cylinder!



I just bought both of them from Peter at South Bend for $90. 00! Peter recommended that for the $30 the slave cylinder cost to replace it along with the $60 clutch master cylinder. I took his advice, and got my clutch back!



I was having a bleed back problem, clutch would go away after holding it for awhile, like backing my travel trailer in place. It was no fun at all. I'd have to shut the truck off and pump the clutch pedel a couple of times to get my clutch back. I replaced the slave cylinder with a Napa's $90 cylinder, however it didn't solve the problem. The Clutch Master cylinder was the problem.



Call Peter at South Bend, he will fix you up for under $100 for both cylinders!



Thank's Peter for your outstanding customer service and great products!