Like the title says, my transmission is hard to shift. Real notchy, and sometimes a bastard to put into gear or reverse. It's rebuilt, and has maybe 400 miles on it. Running Lucas 50wt oil as recommended. But it just doesn't feel right. In another post I stated I had the clutch pedal adjusted way our to get rid of the slop of no bushing. The clutch seems to release ok, it doesn't crawl when in gear. But I worry it's something else. I will say when I put the transmission back in I fought to put it in the last tiny bit in the pilot bearing. Had to torque it down, but I did it as slowly and gently as I could,and the gap was less than half an inch when I started. Not sure if it was hung up on air or just such a tight fit. Also has a Sb dd clutch, and had the big input shaft put in. Stock shifter. No noise from the clutches, and no noise from the transmission. But I can kinda feel the teeth in third sometimes, is this normal?

Anywho, tell me I'm paranoid and it's all ok. I'm terrified to blow up this transmission, or hurt this truck in any way. I waited seven and a half years to get another cummins, don't want to ruin this one. 

1 hour ago, Ravewolf said:

I will say when I put the transmission back in I fought to put it in the last tiny bit in the pilot bearing. Had to torque it down, but I did it as slowly and gently as I could,and the gap was less than half an inch when I started

I would have to say that might be your issue. Things should slip in without forcing anything other than a heavy transmission. Other than that have you tried different fluid.

Might have something misaligned or putting stress on the pilot bearing with misalignment. Little trick learned by two people. 

 

1. When you get that point where you know the tip of the input shaft is just barely starting in the pilot bearing. You now take 4 long bolts the same thread and without heads. Now thread all 4 guide pins in the bell housing. This ensures that transmission angle is now correct but cannot be forced into place. 

 

2. Being it just won't go any farther now hook up the clutch slave cylinder. Have a second guy press the clutch to the floor. This will release the friction disc and typically the transmission falls into place with little effort. This is because of the alignment tool is typically loose and not a perfect center, so the input shaft won't line up with the pilot. I no longer use the alignment tools and go strictly on feel of the friction disc edge measure by feel. 

 

Being you used the bolts to pull it in you most likely have stress on the pilot bearing causing your odd shift issues. 

 

50 WT fluid shouldn't make any difference. I'm just about to cross 100k miles on 50 WT and no issues to this day still shift great even in 0*F weather now and transmission temps never moving the gauge off 100*F. It's not the fluid. I say the input shaft is bound up from being forced in.

13 minutes ago, Mopar1973Man said:

 

 I no longer use the alignment tools and go strictly on feel of the friction disc edge measure by feel. 

 

Being you used the bolts to pull it in you most likely have stress on the pilot bearing causing your odd shift issues. 

 

 

 

I agree. However with a twin disk you do need the tool to align the splines. Don't ever force a transmission install. Are your dowels good? Is the pilot bearing a stock one with the exposed needles or a sealed aftermarket ball bearing? If it is stock I would suspect damage, maybe even partially collapsed or pushed out of the flywheel. Are your hydraulics good? Is this a new clutch or existing one? Just curious but why twin disk?

Just now, NIsaacs said:

However with a twin disk you do need the tool to align the splines.

 

Twins yeah... Different story I'm only dealing with singles friction disc typically. (Rancher and construction trucks)

 

1 minute ago, NIsaacs said:

Is the pilot bearing a stock one with the exposed needles or a sealed aftermarket ball bearing? If it is stock I would suspect damage, maybe even partially collapsed or pushed out of the flywheel.

 

Both versions can be damaged by forcing transmission with the bolts. Aftermarket you can force them out the back or cock the bearing slightly causing drag on the input shaft and bind in the bearing. Stock pilot bearing are not forgiving and don't take much to damage them at all.

 

Forcing a transmission in with the bolts is an absolute no-no. It should meet the face of the bell housing with only hand pressure!

New sealed pilot bearing. I got as close as I could to the bellhousing, then started all 4 bolts, then slowly sucked it in. The clutch and hydraulics came with the clutch. 

I won't have time or money to replace the pilot bearing right away, so how long will it ride? I am going to be traveling to North Dakota soon for work, and I can have a shop replace it for me while I'm there. Unless there's a guarantee of failure before then.... 

Also, I installed the bellhousing first, then the transmission. Was this the correct order? Not much room under there and it was a pita the first time around. Not keen on doing it again honestly. 

Just going to have shift issues till you look at that pilot bearing. Basically, the input shaft is getting some spinning force from the crank so the syncro's are working harder to sync the gears up. It will most likely hold up just not optimal shift quality. 

 

That is something I'm running across is a lot of blaming the fuilds for poor assembly of the clutch. So to make up for the poor assembly of the clutch they require thinner lubricant to bring the shift quality back. I know what you talking about because when I started with the 50 WT lubes I had the transmission rebuilt and main shaft replaced. Installed the transmission on a worn clutch my shift quality was like you said kind of notchy and rough feeling. My pilot bearing was most likle getting a bit dry. After the clutch failed in 2007 and I replaced it all South Bend Con OFE again. Smooth as silk. That transmission was hand pushed into place and works awesome. 

 

OP installed a dual disc South Bend which is KNOWN for being notchy and a bit harder to shift even South Bend was very clear in explaining this to me hence why I tend to favor the single disc. 

17 minutes ago, Ravewolf said:

 

Also, I installed the bellhousing first, then the transmission. Was this the correct order? Not much room under there and it was a pita the first time around. Not keen on doing it again honestly. 

 

That's plumb fine when you have that choice, with the one piece NV5600 you don't. As far as how long it will last, that depends on what is wrong. You don't want to damage the input shaft. Again, how are your dowel pins? Make sure that one or both are not pushed back threw the clutch housing. Since the housing was installed without the tranny, you are probably okay, but be sure. I have even found them missing.

It's all about alignment of the input shaft to the crank basically. 

34 minutes ago, Mopar1973Man said:

Just going to have shift issues till you look at that pilot bearing. Basically, the input shaft is getting some spinning force from the crank so the syncro's are working harder to sync the gears up. It will most likely hold up just not optimal shift quality. 

 

That is something I'm running across is a lot of blaming the fuilds for poor assembly of the clutch. So to make up for the poor assembly of the clutch they require thinner lubricant to bring the shift quality back. I know what you talking about because when I started with the 50 WT lubes I had the transmission rebuilt and main shaft replaced. Installed the transmission on a worn clutch my shift quality was like you said kind of notchy and rough feeling. My pilot bearing was most likle getting a bit dry. After the clutch failed in 2007 and I replaced it all South Bend Con OFE again. Smooth as silk. That transmission was hand pushed into place and works awesome. 

 

OP installed a dual disc South Bend which is KNOWN for being notchy and a bit harder to shift even South Bend was very clear in explaining this to me hence why I tend to favor the single disc. 

The clutch and hydraulics came with the truck I meant to say. I didn't buy them. 

Will a single disc hold up to power? What is the limit for them? I plan on building the truck more in the near future. 

Single disc clutches hold up just fine as long as you don't torque trap the driveline which you've done. When you add 33 inch tires you now lowered the final ratio (3.40:1) to the ground placing more stress on the driveline and the clutch. I did the very opposite and went to a smaller tire and raised my final ratio to (3.69:1) and allowed the tires to break free before the clutch does. I'd rather spin the tires lose than break the main shaft or spin a clutch. 

 

 

If the input shaft is misaligned it will put added stress on the input shaft bearing at the front of the case and cause premature failure.    

1 hour ago, Ravewolf said:

The clutch and hydraulics came with the truck I meant to say. I didn't buy them. 

 

 

Did you remove and inspect the clutch and pilot bearing while the tranny was out or just R&R the tranny? How far from the floor with the clutch peddle do you feel engagement/truck starting to move? One little air bubble in the hydraulics can cause release issues. 

4 hours ago, Ravewolf said:

In another post I stated I had the clutch pedal adjusted way our to get rid of the slop of no bushing. The clutch seems to release ok, it doesn't crawl when in gear.

 

What bushing are you referring to?  With the engine at idle (cold or warm) with clutch engaged in neutral (foot off pedal), can you depress the clutch pedal, pause for a couple of seconds, and then easily select a gear from neutral repeatedly?  If the answer is yes, then the pilot bearing is not likely causing any problems.

 

4 hours ago, Ravewolf said:

Also has a Sb dd clutch, and had the big input shaft put in. Stock shifter. No noise from the clutches, and no noise from the transmission. But I can kinda feel the teeth in third sometimes, is this normal?

 

A rebuilt transmission can feel notchy for awhile depending on how involved the rebuild was.  A notchy shifter combined with a dual disc clutch will affect your shift  timing, especially when upshifting.  The transmission synchro is not designed to handle mismatched road to engine speed during a shift  with the added weight of a dual disc clutch setup, hence "you kinda feel the teeth in third sometimes".

 

If you decide to drive the truck as is for awhile, be deliberate in your shifting method and match engine speed to road speed for the selected gear when upshifting or downshifting.

 

- John

 

41 minutes ago, NIsaacs said:

 

Did you remove and inspect the clutch and pilot bearing while the tranny was out or just R&R the tranny? How far from the floor with the clutch peddle do you feel engagement/truck starting to move? One little air bubble in the hydraulics can cause release issues. 

Yes, I sent both disks off to SB to get re hubbed for the bigger input shaft, and installed the new pilot bearing that came with it. Clutch engages a little under halfway up, maybe lower. 

35 minutes ago, Tractorman said:

 

What bushing are you referring to?  With the engine at idle (cold or warm) with clutch engaged in neutral (foot off pedal), can you depress the clutch pedal, pause for a couple of seconds, and then easily select a gear from neutral repeatedly?  If the answer is yes, then the pilot bearing is not likely causing any problems.

 

 

A rebuilt transmission can feel notchy for awhile depending on how involved the rebuild was.  A notchy shifter combined with a dual disc clutch will affect your shift  timing, especially when upshifting.  The transmission synchro is not designed to handle mismatched road to engine speed during a shift  with the added weight of a dual disc clutch setup, hence "you kinda feel the teeth in third sometimes".

 

If you decide to drive the truck as is for awhile, be deliberate in your shifting method and match engine speed to road speed for the selected gear when upshifting or downshifting.

 

- John

 

It was rebuilt by SuoerStick Transmissions, and pretty much a total rebuild as my tranny burned up from lack of oil (my fault for not checking), and new synchros, new updated mainshaft, new counter shaft, new and bigger input shaft, and 5th gear fix, along with a new top cover (mine was cracked apparently. 

35 minutes ago, Ravewolf said:

It was rebuilt by SuoerStick Transmissions, and pretty much a total rebuild as my tranny burned up from lack of oil (my fault for not checking), and new synchros, new updated mainshaft, new counter shaft, new and bigger input shaft, and 5th gear fix, along with a new top cover (mine was cracked apparently.

 

So lots of new parts went into the transmission.  You didn't specifically answer my question regarding shifting into gear from neutral at idle.  Assuming that it shifts into gear easily and the only problem you really have is difficulty in shifting, try driving it for awhile in the manner I suggested in my earlier post.  You may find the transmission gets easier to shift as the miles roll by.

 

- John

4 hours ago, Ravewolf said:

Will a single disc hold up to power? What is the limit for them? I plan on building the truck more in the near future. 

Single disk won't hold up to the mods you already have, unless you reallly baby it. Best to have the dual disk from your point on if you want to keep building it.

Edited November 14, 20186 yr by trreed

On 11/14/2018 at 11:13 AM, Tractorman said:

 

So lots of new parts went into the transmission.  You didn't specifically answer my question regarding shifting into gear from neutral at idle.  Assuming that it shifts into gear easily and the only problem you really have is difficulty in shifting, try driving it for awhile in the manner I suggested in my earlier post.  You may find the transmission gets easier to shift as the miles roll by.

 

- John

I tried that trick, it seems to work somewhat at first. But still sometimes it's kinda hard, and I have to keep playing with the clutch to get it to go in. 

I've also found out if I move the stick in neutral back and forth a few times she drops right in. 

Just shits and giggles I doubled clutched all day yesterday, and she shifted beautifully. So I'm thinking she still needs to break in a bit still. 

 

You'll all come to see I tend to panic over little things. Like my truck now decided she wants to lope a few times while idling, and sputtering while free revving. Fml. No tests yet because no time, working on other people's cars at the moment. 

3 minutes ago, Ravewolf said:

Just shits and giggles I doubled clutched all day yesterday, and she shifted beautifully. So I'm thinking she still needs to break in a bit still. 

 

Dual disc clutch tend to have more rotational mass and the syncro's can't slow down the input shaft fast enough because of the rotational mass of the dual disc. What you doing with double clutching is giving the discs enough time to slow down and syncro's can do there job now. 

2 minutes ago, Mopar1973Man said:

 

Dual disc clutch tend to have more rotational mass and the syncro's can't slow down the input shaft fast enough because of the rotational mass of the dual disc. What you doing with double clutching is giving the discs enough time to slow down and syncro's can do there job now. 

I was also thinking along that train of thought too. Either way I'll keep double clutching until further notice. 

5 minutes ago, Ravewolf said:

I was also thinking along that train of thought too. Either way I'll keep double clutching until further notice. 

 

This is why you can't judge the 50 WT transmission fluid as a cause being you've added more rotational mass in your clutch. Then blame the fluid. Very very common. Now if you had a single disc clutch you would see the very same thing I do with good shift quality. 

 

Way too many time people claim they changed fluids attempting to resolve a shift problem beforehand and then the problem worsens after the fluid change and the blame is tossed on the fluid instantly. When in fact the majority of the time the shift problem is a pre-existing clutch issue or pilot bearing issues. 

 

Personally, I think the 50 WT will provide better protection overall being the lubricant is much thicker and withstands temperature better than a thinner grade of lubricant that would get too thin in heavy towing or high summer heat. Being 50 WT transmission fluid is designed around the Eaton Fuller transmissions and hauling 80,000-pound loads. It should be a piece of cake for the 50 WT to do its job for a mere 8,000-pound truck.