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Hard Shifting NV4500, less than 2 years on clutch

When you had it all apart, signs of a bad flywheel would include areas of where it was blue - indicating overheating/possible high spots on the surface, scoring or any fine cracking.

You still haven't really described very well what exactly your 'hard shifting' issues have been. Is it grinding between shifts, getting it into gear from Neutral, getting in/out of Reverse, the vehicle still moving forward/backward when in gear (1 or R) with the clutch fully depressed, hard to move the shift lever when shifting between all/certain gears?

With a syncromesh manual transmission, you can be rolling down the road and upshift without using the clutch (and downshift if you blip the throttle to bring up rpms). I did that with my old '80 Subaru 4WD when the clutch cable broke between paychecks back in college and was driving around town. There was a little grind and a lurch from N to 1 at a stoplight, but that was about it.
 
Peter, I highly doubt anything is wrong with your tranny, plan and simple your clutch isn't fully disengaging, I thought the bearing instructions stated 1/16" clearance ? I set mine @ 1/16" , and my master rod, the adjustable one, allows me to increase or raise the petal so I get more travel and don't need to mash it on the floor, and my NEW fork was cracked so I strengthened it... remember everything is china made with nearly no quality... and if your flywheel is a bit thin it's not sitting as close to the tranny as it should be so that's a place to find less travel.

If the tranny will go into gear with the motor off and is hard with it running the clutch is dragging..
 
I doubt the problem is the transmission too, just stumped as to why I'm having so much trouble.

@Husker6.5 the transmission is impossible to get into gear with the truck idling at a stop. I've had to stop driving it this week as I need to shut the truck off to put it into 2nd gear to get moving. I can fight it into 3rd and then from 3rd it goes into 4th a bit more easily from there. It doesn't grind at all, just literally can't get it into gear. Clutch is most definitely dragging.

@Twisted Steel Performance the instructions said to adjust for clearance of 1/16" to 1/8". I opted for the safer side of 1/8" as a little more pedal travel was preferable to me over having the bearing too long and riding the clutch all the time. Since it still came out 1/4" longer than stock I figured I was still in the ballpark and not over or under- doing anything.

Also Chris where is the flywheel shimmed, on the backside where it bolts to the crank? That flywheel came off my '99 engine that threw a rod so I have no idea how much or how long ago it was shimmed. Does at least let me know that it was turned at least once and that the flywheel probably isn't the issue. If going through all the trouble of getting to the flywheel again I'd suck it up and put in a new one, but I do really appreciate you remembering and letting me know it's already been turned/ shimmed :)

It's freezing outside and I don't have the motivation to crawl under the truck in the gravel and bleed the slave, will do so tomorrow.

There's no way the long snout pilot bushing would be an issue here? Didn't take any pictures but can't remember if it was flush with the inner face or slightly recessed in, definitely wasn't protruding though.
 
When I got your motor the shim was on the outer side like a washer would be, but I knew that was wrong and I put it between the wheel and crank, that would have moved the wheel towards the tranny... and the flywheel didn't look that great but I didn't look really hard...

I never had any luck bleeding the system on the truck, even on the bench it takes many pumps to get all the air out... I know how hard the stock line is to get on and off, thus I opted for the braided flex line and got it longer than he makes them for conversion's ...

If I were you, I'd get the flex line and a adjustable rod, you will need to send him your rod, and give that a try, it's less work and money...
 
as it is now, when you start the truck while in 1st gear and clutch to the floor, and foot off the break on a flat semi-level area. how far do you have to release the clutch until you begin to feel the truck barley start inching forward? if it's just a little bit or you already feel it tug forward while cranking, you need more travel in the slave cylinder or the bearing isn't adjusted outward enough. iirc you need to have at least 1/4 to 1/2 pedal travel upward before the truck begins to move. but then again it's been a while since I've messed with a clutch!
 
oh yeah I remember the horrors of bleeding clutches! I recall having to step on it like 20 times before having someone crack the bleeder screw. then it was every third crack of the bleeder refilling the fluid. when I was wrenching on cars back then, I remember having to apply return pressure on the slave rods just after cracking the bleeder just so the master would begin building pressure again.
 
As is now the truck will creep while starting with clutch fully depressed and foot off brake. Clutch definitely isn't disengaging.

I've successfully bled the system before, both by pumping the slave from underneath and using the bleeder on the slave.

When I did the clutch last April I bled using the bleeder (had a friend to help at the time, haven't been able to corral anyone yet this time around) and the clutch felt great.

When the hard shifting started a week or so before the swap, I thought I had found the culprit when the fork pivot stud was broken off.

Now with everything new and the same issue present, I'm very confused.

I did order a braided stainless line off Rock Auto. Never liked how the hard lines always routed so close to the crossover pipe, imagine a lot of slaves were ruined from fluid heating up in the line and blowing seals. I've always had some kind of heat shield tape/ loom on the line around the cross over pipe to mitigate this.
 
how much end free play do you have on the pedal? when grab the pedal and pull up on it vs when it's resting on the rod linkage from the master? it should only have I think maybe 1/2 inch or so maybe less.
 
I'm thinking there is still air trapped in there somewhere or something isn't right with the travel, slave rod length or something. have a helper pump the pedal while you're under there bleeding and watching things. I can't say for this particular tranny, but most that I have messed with that use the external slave cylinder, when the pedal is pushed to the floor the fork portion that sticks out of the tranny should almost travel completely to it's limit where it just about comes in contact with the bell housing. since your bearing is adjustable and stock is a fixed distance, there may also be something there where the fork sits at a slightly different position than it would with a stock bearing. this would cause the slave not to travel fully inward when released hence why you would need a longer rod on the slave. I have seen hillbilly's use an old lifter push rod in the place as a rod on the slave before just to get somewhere lol. something you can try is when the pedal is fully released, grab you a pair of vice grips on the rod and try pushing it further into the slave. if you are able to gain a gap between the fork and the rod, then this is what is happening. that area of travel you are able to push it will also be where there is an air pocket!
 
I am officially out of ideas and going to have to take the truck to a nearby shop.

Stainless braided hydraulic clutch line arrived while I was out of town for the holidays. Pulled master and slave this morning. Bench bled as described. Confident there is no air in the system.

The stainless braided line from RockAuto is awesome by the way, made installing the entire system a breeze.

Installed everything, fired it up. and no difference. Can't put into gear with the truck running. Clutch is not disengaging.

I turned the truck off, blocked the clutch pedal with a piece of wood and climbed under to inspect what I can through the bellhousing.

The slave travels about halfway past the inspection hole. I can see the fork pressing the bearing into the pressure plate fingers past the face of the smooth outside edge of the pressure plate. So I don't think slave or fork travel is the issue.

I can also see the pressure plate flexing from underneath through the three bottom holes on the bellhousing. And can see the clutch still touching the flywheel. Not sure how much gap is supposed to be visible, but for reasons still unknown to me the clutch will not disengage.

Is the ANYTHING else that should be looked into? I am baffled that the same clutch disengagement issue is still present after changing literally everything except the flywheel. I don't know if I should suspect the long snout pilot bushing either, but I don't see how that would prevent movement of the clutch, only possibly grab the transmission input shaft and keep it from slowing down.

:banghead:
 
Just for grins, on that adjustable bearing, did you have any more adjustment where you can make it push further on the clutch. maybe adjust it out where it's riding on the fingers on the pressure plate slightly to have that little bit of extra travel and try it in the driveway? that might tell you more so if it's in the clutch it's self maybe a defective pressure plate.

edit: another thought, is the fork flexing when pressing the clutch. that you would only see while watching it move as someone was pressing and releasing the pedal.
 
@dbrannon79 I could have adjusted the bearing out further, but it's put together with loctite and roll pins, and not accessible without pulling the trans and bellhousing, so adjusting isn't really an option.

Not really sure if I can tell if the fork is flexing from looking underneath, although the fork is new. The Dorman and GM OEM versions look identical in terms of thickness, material etc.

A neighbor is coming over to depress the clutch while I make the last ditch effort to bleed from underneath. For better or worse it seems a shop is going to have to pull the trans and bellhousing and diagnose why the clutch isn't separating from the flywheel.
 
I've installed THOUSANDS of Dorman parts with little to know issue. Nothing wrong with their quality.

This is a weird issue.... I'm kinda out of ideas myself, and its hard to diagnose something like this over the internet. Hopefully your local shop can figure it out for you. Keep us updated!
 
Sometimes Dorman is the only part available, not my first choice but aside from the fork ball stud breaking I've never had an issue with them either.

Bleeding from underneath didn't help, no air visible in the system from what I let out.

In holding up the old slave next to the new one in the bellhousing, it seems the slave rod can travel a lot further than its current maxed out pedal position. I'm going to peek at the slave travel on another truck with the same trans & slave configuration and see if there is any difference there.

I also haven't really looked at the clutch pedal itself, first inch or so of travel doesn't really move the slave at all but it's not sloppy or anything. Maybe it is something as silly/ stupid as a worn clutch pedal assembly.

@ak diesel driver hard to see gap between bearing and fingers exactly, been meaning to bug a plumber friend with a probe/ scope camera to get up in there and see. I already set the adjustable bearing at 1/4" larger than stock, so I don't think that is the issue. If anything I'm still skeptical of the extra protruding threads interfering, but the folks at Novak assured me this isn't an issue, and @Twisted Steel Performance using the same bearing (albeit his is 1/2" larger than stock) agrees with their assessment.

Will definitely provide any positive updates on this headache
 
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