Timken Clutch Release bearing, NV5600

[Darkbloodmon]

Also, 50 in 4th won’t produce 3800 rpms. Sounds like you meant 3rd. 50in 4th is ~2800 rpms. Which brings up another point, if you’re trying to grab 4th at 50 it’s going to be a difficult downshift unless you blip the throttle up.

I was going 50 in 5th coasting and breaking down to 40, near 40 I attempted to down shift into 4th. Engine over speed up too 3800 as I let out the clutch. Maybe my tach and speedo are off kilter?

I always blip the throttle when I down shift whether its a double clutch or standard down shift while in gear. I've not taken any driving courses but I learned stick on this truck and blipping the throttle from my understanding was the standard procedure for downshifting.

If you think the hubs won't make a difference then I won't bother with them.

 

[CVR222NV]

Single disk installed yesterday. Test drove over 108+ miles this morning.

I'm not going to lie to you, its not 100% but it's a hell of alot better. The single disk overall is night and day in shifting and engagement, near effortless compared to the dual disk. I can consistently down shift into forth and third around town. This issue still remains in downshifting from 5th at highway speeds into traffic or for off ramps. Point of note my idle speed at operating temp in neutral is back down to 750, the dual disks weight bumped the idle up to around 8-850.

Speed is a variable, I managed to pull it into 4th on the highway as I was slowing down from around 50mph and my engine speed was over run by the wheel speed. I hit 3800rpms as I let out the clutch; no engine damage, no valve contact.

I drove back over to Standard Transmission and Gear with 2 dozen Doughnuts from Dunkin as a small thank you for their time and assistance in the past week and half. Took one last test drive with Juaquin around Fort Worth to verify all the engagement noises I was hearing were normal and let them know I'll be heading back east tomorrow morning sometime.

I don't have any more time or money to spend in Texas for this issue. The single disk is much more manageable and consistent. Street and city speeds are perfectly fine down shifting into 4th and 3rd. Highway off ramps or getting into 4th from 5th while slowing down is going to have to be a feature. STG doesn't have an answer, but we both agree that speed is a variable. For what its worth I'm much more happy with the 1947-OK-HD. Everything from top to bottom has been gone through and the issue persists.

For clarity's sake with the single disk. I have no issue on the street 50mph and lower down shifting into 4th or 3rd. My downshifts are well timed and smooth, you can almost slap it in. This changes as I'm slowing down from highway speeds, I could be in 5th gear decelerating from 50mph to 40mph and attempt a down shift to 4th and It will not go in. The dual disk gave me issues on the street downshifting into 4th and 3rd, consistently to a point where I had to focus my shifts. I can let my hands and feet do the thinking with the single disk now.

I'll write up a final conclusion after I get back home and finish the 500mi break in period of the clutch in stop and go traffic around town. I'll give South Bend a call after I get back home and see what they think. Unless the clutch, transmission, or transfer case grenades' its staying in. All my warranties still stand.

There is one variable unaccounted for that preludes my shifting issues with both the South Bend Clutch dual disk and single disk. My Spyntech locking hubs. I was thinking about this earlier as I found myself laying frame (like all the pretty Chevys I see down here) stuck in mud in a highway shoulder. I was on my test drive this morning and an important call came in from a relative out of the country. I pulled over quickly and thought to go onto the grass as the two lane highway was moving pretty fast. The grass was a trough of deep mud. Nothing I did was moving me as my right side wheels were churning batter. A class 8 truck driver pulled over and yanked me up and out God bless him. I wish I had the cash to give him for his time, but I'll just have to pay it forward to someone else when the circumstance allows me.

Too the point, the Dodge AAM 9.25 front axle is live and puts resistance on the transfer case and transmission as it rotates. That's all done away with when locking hubs are installed. My thought process is the weight and rotating resistance of the front axle rotating assemblies would not only bring my drive train speed(gear rotating assembly) down quicker but maybe in a more shift-able range. I'll try locking my hubs in on the highway after the clutch break in back home and see if it makes any difference. Thoughts?

Otherwise this thread will just be an unsolved riddle once its filed away in the archives.

Here are a few pictures of my truck with "Texas" mud for your viewing pleasure. Tire( Toyo Open Country AT 2s) pressure was 55/50 as per recommendation in a different thread. Enough mud packed my right front wheel to cause an imbalance.
View attachment 131572 View attachment 131573 View attachment 131574 View attachment 131575 View attachment 131576 View attachment 131577

Are you still running stock differentials? The stock front differential is open and worthless in mud like that. Even the stock rear end with posi is questionable in those conditions. Ask me how I know! Probably no reason to have the hubs locked on the highway unless in snow or ice conditions.

 

[AH64ID]

I was going 50 in 5th coasting and breaking down to 40, near 40 I attempted to down shift into 4th. Engine over speed up too 3800 as I let out the clutch. Maybe my tach and speedo are off kilter?

I always blip the throttle when I down shift whether its a double clutch or standard down shift while in gear. I've not taken any driving courses but I learned stick on this truck and blipping the throttle from my understanding was the standard procedure for downshifting.

If you think the hubs won't make a difference then I won't bother with them.

You shouldn’t get above 2800 at 50 in 4th unless you gave it a lot of fuel, and even that shouldn’t come close to 3800. Short of being in a lower gear than you thought, or a gauge, I don’t see how you could get the rpms that high.

Only on downshifts where I was trying to get into a lower gear above 2500 rpms did I have to blip the throttle, and even that wasn’t always needed. Bliping the throttle to down shift wasn’t standard for me. I never double clutched my NV5600.

 

[Darkbloodmon]

Are you still running stock differentials? The stock front differential is open and worthless in mud like that. Even the stock rear end with posi is questionable in those conditions. Ask me how I know! Probably no reason to have the hubs locked on the highway unless in snow or ice conditions.

Stock 3.73s and a rear Anti spin torsional according to the Vin build sheet, I resealed the front diffs leaking pinion and it has new fluid and a cover gasket. Rear has fluid topped off, Rear axle has new hub bearings and races. Nothing else done.

 

[Darkbloodmon]

I don’t see how you could get the rpms that high.

The engine over sped a good bit. I was definitely in 5th coming down from 50mph double clutching into 4th with a blip as I usually do. I don't shift at a high rpm but when my tach needle went past 3500 my eyes bulged as I pressed the clutch in.

I'll take note of my rpms by gear on my drive back.

 

[GCroyle]

DBM,

Good news, head for home and enjoy the ride.

I think it would take an engineer to do the math of the inertia of a spinning single 13" disc with organic facings vs buttons and then do the same for a twin disc organic and buttons. Care to guess which of those has the most inertia if the facings are the only changes?

A long time ago a certain well known name clutch company (no longer active AFAIK) had a line of metallic faced discs, more power etc etc but in smaller trans they shifted like garbage due to the high inertia of a heavier spinning disc vs a light one.

Nice you took a thank you to STG.

Gary

 

[bcbender]

Bliping the throttle to down shift wasn’t standard for me. I never double clutched my NV5600.

Agreed.. no need to do, I never did until I was having issues with synros, but that was due to no pilot bearing and a damage input shaft.

 

[BigPapa]

I never double clutched my NV5600.

I don't understand the double clutching, either. I thought double clutching was for clapped out transmission's and old transmission's without full synchronization.

 

[bcbender]

yep... I only did it when driving unsynchronized class 8 trucks, and not always then, a lot of the time I could just tap the throttle to bring the engine speed up on down shifting and match it on decel when upshifting... IMHO no need on the RAM trucks

 

[Tuesdak]

I have always said the NV5600 was slow shifting. I would just hold it on the syncro until I could feel it was ready to drop in. I would double clutch it if I was in a hurry to downshift. No reason to push all the wear on the syncros. The rebuild got rid of the notchy feeling for me.

I have missed 4th before. Esp. with a sloppy bushing on the shifter. The REV to the MOON sound before you let the clutch out is a clue you grabbed the wrong downshift gear.

 

[Darkbloodmon]

Just got back in moments ago. God bless NCDOT the roads feel so much smoother. I didn't know what I was missing.

No issues, no break downs, very nice ride overall. I was able to get some smooth down shifts into 4th gear from highway speeds pulling into a 3 rest stops but I'm going to hold my breath before any final conclusion till I break the clutch in in stop and go traffic for 500 miles.

I don't understand the double clutching, either. I thought double clutching was for clapped out transmission's and old transmission's without full synchronization.

Correct, I don't do it consciously 100% of the time, its a mixture. But its become a habit of my hands and feet since I've learned it. I'm self taught on stick with this truck and I just stick (haha) with what feels good and engages well. I only double clutch my down shifts.

Nice you took a thank you to STG.

It's the least I could do after picking their brains over every sound and detail for the past week and a half.

 

[NIsaacs]

I was able to get some smooth down shifts into 4th gear from highway speeds pulling into a 3 rest stops

At what speed are you shifting to 4th? Using the transmission with multiple down shifts to slow an empty truck is a waste of energy. Going from 6th to 5th at about 50 is fine, then 5th is low enough until your speed drops to about 30 mph, then you can slip it into 4th.

You mentioned some hotshot work. I recommend you find a heavy load to tow, drive through town with a bunch of stop lights, then find some hills and see how everything works out for you. Empty might not be a good enough test.

 

[bcbender]

yeah... I used to put it in direct (5th) and let the exh brake do all the work... then 4th if needed but usually was slow enough to use service brakes from there.

 

[AH64ID]

Same here, unless I was heavy or trying to hold speed with the EB.

 

[Darkbloodmon]

At what speed are you shifting to 4th?

I'll down shift to 5th anywhere from 70 to 60 and I'll engine brake down to about 40 before I down shift again to 4th.

I recommend you find a heavy load to tow, drive through town with a bunch of stop lights, then find some hills and see how everything works out for you. Empty might not be a good enough test.

Fair point, all my driving has been unloaded so far. A good friend whos helped me with this truck has a trail built XJ he tows around to 4x4 parks I'll ask him if I can pull it to a local event after I get my clutch fan situation resolved.

 

[AH64ID]

@Darkbloodmon do you have an exhaust brake?

 

[Darkbloodmon]

@Darkbloodmon do you have an exhaust brake?

I don't. The previous 4 owners didn't use one either when pulling a 5th wheel; Turbo was factory and spent when I got it. All stock except an intake and trailer brake.

 

[AH64ID]

I don't. The previous 4 owners didn't use one either when pulling a 5th wheel; Turbo was factory and spent when I got it. All stock except an intake and trailer brake.

That should be, or have been, your #1 priority upgrade for how you plan to use the truck.

The previous 4 owners were a bad example for you.

 

[bcbender]

Pac-Brake PRXB IMHO was one of the best upgrades I did on the truck..... Id say even better than more power...

I'll down shift to 5th anywhere from 70 to 60

Not sure about the 3:73 trucks, but mine was RPM limited at 60 in 5th (4:10) so shifting in a 70 seems like you'd be close to maxed out and would inherently be hard to shift anyways.

 

[AH64ID]

Not sure about the 3:73 trucks, but mine was RPM limited at 60 in 5th (4:10) so shifting in a 70 seems like you'd be close to maxed out and would inherently be hard to shift anyways.

With 3.73's and the 285/70R17's that the OP is running 3rd redlines at ~40, 4th at ~ 58, 5th at ~81, and 6th at ~111.

70 is 2000 in 6th and 2770 in 5th, which is difficult to grab.