Archived Hard gear shifting G56

[SquareDave]

2006 Ram 2500 G56 (210,000 miles)

Hard or impossible shifting after 10-15 miles. Shifts smoothly at first after initial startup. Also shifts easily when engine is not running.

Shifting into reverse sometimes requires the engine to be shut off.
Upon restart, clutch starts engaging as soon as I begin releasing pressure off the pedal.

Clutch kit (with flywheel conversion) is new. Hydraulic linkage is new.

It's like the unadjustable needs to be adjusted, but I know it can't. What could we be missing here? Worn fork or something else?

 

[BigPapa]

Pilot bearing, damaged or worn input shaft, improper installation, incorrect clutch kit, incorrect hydraulics, etc.

My money's on the pilot bearing or input shaft.

 

[SquareDave]

More info on transmission issue

I drove 160 miles Saturday and observed symptoms for several scenarios when drivetrain had been operating for a while..

1) Gong forward in town, on the highway, or in construction zones shifting was smooth 2nd-6th gears. Did not use 1st.

2) Stopped at rest area and pulled forward into parking place at curb. Could not shift into reverse while engine was running.

3) To back our of parking place I shifted into reverse with engine off. Backed out with no problem. Had trouble shifting into any of the forward speeds while engine was running. I finally managed to get into 3rd gear even though it resisted - no grinding of gears, but the transmission would not go into any gear except 3rd.

4) To back into driveway at home, I was able to shift into reverse with engine running, but there was a lot of resistance (no grinding). After backing into spot I tried shifting into all the gears. This time I was able to shift into every gear including reverse, but it was not smooth. With engine off the shifting was much easier.

As long as I'm going in one direction, everything works like you would expect. The challenge starts when I need to back up after I've driven a few miles. I'm less afraid to take the truck on the road, but I'm still not comfortable.

 

[GCroyle]

2006 Ram 2500 G56 (210,000 miles)

Upon restart, clutch starts engaging as soon as I begin releasing pressure off the pedal.

Clutch kit (with flywheel conversion) is new. Hydraulic linkage is new.

From that info alone, I'd investigate for an air bubble in the hydros. It's really your only possible external fix.

Assuming decent shop skills, remove the slave cylinder, remove dust boot and pushrod, attach steering wheel puller to face of slave cyl, bolts just snug no wrenches. Turn the puller screw it to just make contact and block the piston.

Now, use your hand and push on clutch pedal. The test is how far does the master cyl pushrod travel before you feel a good solid hydraulic pressure.

If you have a stock bells and whistles G56 hydro, about 3/16" or less pushrod travel, if the system doesn't have the B&W stuff, 1/8" is possible.

Any travel greater than those dimensions confirms air in hydros. And restating, use your hand only, not your boot!

If air is confirmed, remove entire hydro system and one piece.

Go to work bench.

Master cyl must be positioned pushrod end pointed down from horizontal 30-45 degrees, remove reservoir cap. I use a bench vise and just lightly pinch on the area where the line connects.

Stretch out line slightly, point slv cyl straight down, insert 3/8" X 8" extension in puller hole, slowly push down compressing the slv cyl piston in completely. Have observer watch fluid for bubbles.

Repeat several cycles, pushing air out, pulling fluid in.

Reinstall puller screw. Recheck for pushrod travel.

These master cyl's trap air, it will not come out as long as its horizontal.

Reinstall.

Engine running, select 1st gear, now how far does the pedal come up before you feel the truck move? It's called reserve travel, should be 1 1/2" give or take.

You can also check the pedal pin that pushes on the master cyl push rod too for wear.

Gary

 

[SquareDave]

Thanks. The bad news is there were no bubbles in the hydraulics. Replaced the hydraulics anyway - no change. Next step is to look at the clutch kit itself focusing on pilot bearing.

 

[SquareDave]

Thanks. Shop will be focusing on pilot bearing tomorrow as well as the clutch itself. Hopefully, the input shaft has not be damaged during this ordeal.

 

[GCroyle]

Your comments indicate that you didn't TEST the hydraulic system. The push rod test is a definitive assessment of the hydraulics.

 

[NIsaacs]

Thanks. Shop will be focusing on pilot bearing tomorrow as well as the clutch itself. Hopefully, the input shaft has not be damaged during this ordeal.

I doubt it is the pilot bearing, it was new, right? Since you changed the flywheel, I am sure a new one was installed with it. Were both hydraulic systems complete sealed units? Look real close at the input shaft splines for wear.

Nick

 

[mweiman]

Also take a good look at the clutch pedal to make sure there is not wear in the upper bushing or somewhere that the pedal is not pushing the hydraulics the full length. Just ran into this on a higher mileage ford top bushing was worn out on the pedal, it would move a couple inches before it actually pushed the hydraulics in.

 

[BigPapa]

What hydraulics did you install? Brand and/or part number if you can.

 

[EDankievitch]

Wasn't there a write up about this same problem in ether the last issue of TDR or the one before it. I seem to remember hard shifting and there being a spacer on the crank that pushed the flywheel out too far.....

 

[GCroyle]

Wasn't there a write up about this same problem in ether the last issue of TDR or the one before it. I seem to remember hard shifting and there being a spacer on the crank that pushed the flywheel out too far.....

Yes, SAG2 did that write up. That spacer was accidentally reused when they converted from an aftermarket system to the original DMF based design. That error was the root cause of the problems. It was correct for the aftermarket system but not the OE system.

 

[SquareDave]

All the normal problems were mentioned by everyone involved. This morning the shop called and said they wanted to check something on the installation of the clutch kit. I took the truck in and they investigated what they intended to investigate.
1) Hydraulics good.
2) Flywheel good and to spec. for the vehicle
3) Throwout bearing good.
4) Pilot bearing good.
5) Pressure plate good
6) Clutch plate good.

Upon close examination, it was discovered that a rubber tip had not been not been installed with the kit. When they corrected that oversight, the problem was solved. As soon as I pushed on the clutch I could tell the difference. I took the truck on a 25-30 mile shakedown drive, and it performed flawlessly. The proof in the pudding was that I could shift into reverse easily without killing the engine.

The shop conferred with a number of bona fide experts who missed it, but somebody did suggest what was really the problem.

Thanks for all your input. This has been an education for your's truly.

 

[GCroyle]

Thanks for the follow up, can you be a bit more specific about this "rubber tip". That almost sounds like the cap on the end of the slave cyl pushrod.

Just a comment, a pressure plate can look great and still not work. Testing a pressure plate for release requires a clutch testing machine or setting one up on a flywheel and testing for release as a system. But doing that requires knowing what the test specs are.

 

[NIsaacs]

Thanks for the follow up, can you be a bit more specific about this "rubber tip". That almost sounds like the cap on the end of the slave cyl pushrod.

Yes, more info. Do you suppose someone removed the hard plastic tip with the restraint strap, twice??

Nick

 

[GCroyle]

Nick,

I'm waiting for confirmation, then I'll comment.

Gary

 

[NIsaacs]

Nick,

I'm waiting for confirmation, then I'll comment.

Gary

Thanks Gary, it sure is hard to diagnose anything when we are 1000 miles away

That "rubber tip" has me scratching my head.

Nick

 

[SquareDave]

I'll try to get more detail about the "rubber tip" later this week. The tech who discovered it told me a rubber tip was missing on the sleeve. I was so overjoyed to get the truck back with the problem gone I didn't follow up.. Although the explanation begged the question, I didn't bother to ask it at the time. They did own up to whatever and were probably more glad to get the truck out of the shop than I was to drive it home.

 

[NIsaacs]

I'll try to get more detail about the "rubber tip" later this week. The tech who discovered it told me a rubber tip was missing on the sleeve. I was so overjoyed to get the truck back with the problem gone I didn't follow up.. Although the explanation begged the question, I didn't bother to ask it at the time. They did own up to whatever and were probably more glad to get the truck out of the shop than I was to drive it home.

Thanks, the more info the better, that's how we learn what not to do. If we learn from others mistakes it takes some of the hurt off.

Nick

 

[GCroyle]

Yup, still waiting for clear description of "rubber tip on sleeve". What it is and where it goes.