Transmission oil For 5 speed Manual

[dwsmitha]

Originally Posted by upbeat

Transmission is in a 1974 Crown with Cummins NH-250. Haven't yet found transmission ID. Anyone happen to know off hand? Trying to swing by and pick some up before parts shop closes.

Usual transmission for that vehicle/engine combo is a Fuller T905. An easy lookup.. good luck[emoji6]


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[dwsmitha]

Originally Posted by upbeat

Got underneath this evening.
I've got a Fuller T-905.
Here's the manual: Eaton Transmission Service Manuals in PDF

Sometimes it shifts OK, but most of the time it's terrible. Haven't figured out when it's good yet - either it's slowly getting better since I bought it (maybe it sat for a while?), or it's better when it's cold. At idle in the parking spot tonight I could easily get in and out of 1st from neutral. Often, I can't. Basically I drive it like there's no clutch and match speeds exactly. As long as I drop into 1st while I'm still rolling at 3mph before coming to a complete stop I'm fine. Murder standing on that clutch pedal in rush hour though.

I had hoped it was just low on oil, but I checked tonight - it's full up to the plug. Looks dirty, but it's there (ok, just read the manual, they say just because you can touch oil, it's not necessarily the right level, needs to be at the plug. Will need to check again.)

two other things to note:
1) the clutch is way out of adjustment. Engages at the top 1" of the pedal travel. Doesn't slip - even on SF hills - but never driven a clutch that comes on strong only in the last 10% of travel.
2) The inspection cover on the bottom of the transmission is missing - looks like maybe weather got in there. Seems likely that's why the clutch won't fully disengage and something is dragging.

Need to do something as we're going to use it for a friends wedding in August - rural Sierra wedding, so rig has to be solid. Friend is a machinist, so that's handy. If it works out to install a 10 speed Roadranger, I love those things, and I would do that. Anyone have a rebuilt one lying around? Could put the Roadranger in and then rebuild the Fuller while it's out - because that sounds fun. Open to other simpler options, like just fixing the Fuller.

Thinking some about how to do it. Thinking I might weld a steel frame inside and lift it on a comealong. Could setup a bench inside and rebuild right there. Best would be have the Roadranger sitting on blocks inside ready to drop down. Might get it done in a weekend if I can figure out the clutch and it all comes apart.

Open to suggestions. Also looking for a place in the San Francisco Bay Area where I can park for a week or two while I do the job. Can't do work in the RV storage place I'm using.

Thanks,

Adam

Adam--that transmission has a clutch brake at the bottom of the clutch travel to stop the trans from spinning when you need to get it into first gear. The transmission is twin countershaft, and the clutch is a dual disc model. If you use the clutch for shifting you only need to TOE it at the very top of the travel of the pedal to disengage and engage it. If. You put your foot all the way to the floor when shifting on the move, you will find the shifts difficult (as you are stopping the transmission with the clutch brake), and you will burn the clutch brake out, making shifts into first and reverse at a dead stop fairly difficult if not impossible. I see you got the manual. This SHOULD be detailed in its operation. If not, please get back to me and I'll be happy to share details. Will be in SFO area 22-25 June, and am retired instructor. Best--Deanna


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[upbeat]

Thanks Deanna for the offer to help. I'm spending a few hours working on electrical and the clutch on Sunday, and will have a better idea where I am after that.

For any interested in clutch brakes, there's a good video here:

https://www.youtube.com/watch?v=01ZZ...ature=youtu.be

though Ace-mfg e-mails all bounce. Plenty of other manufacturers. If anyone has a preferred clutch part mfg. let me know. Right now I like the look of AMS

AccessoriesÂ*|Â*HD Clutches | AMS Automotive

and am waiting to hear back.

[upbeat]

Just spent a few hours on the road. I can now say for sure the clutch brake is either out of adjustment, or has been worn out. Most times I can wait for 5 or 10 seconds and then drop in to first, but a few times, especially when it's warm, I just couldn't get into first from a stop without grinding. I know, you're thinking I should just shut it down , shift, and start up, but the engine crank isn't working on the key, so in need to start from the panel in the engine compartment. Step 1, get some new switches installed and then finish debugging the intermittent electrical issues.


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[Booyah45828]

Step 1: get a way to start the bus from the drivers seat.
Step 1a: inspect the clutch and have it adjusted if necessary.

Don't condemn the brake or clutch until it's adjusted. I cannot stress enough in how important the adjustment is to it's performance.

[upbeat]

Hello All,

Update on this thread - had the clutch brake adjusted by a pro. It moved the clutch release point into a "normal" position from the strange position it had been 1" from the top of the pedal travel, but the clutch brake still doesn't slow it down in neutral. A little deceptive since it shifts from neutral fine cold, but once warmed up there's no way not to grind into first, no matter how long you sit with the clutch in.

So it's back in the shop for a second try adjusting the clutch brake.

While we were in we found the differential (aka pumpkin) bolts were a little loose and leaking. Mechanic suggests we drop the shaft, re-pack the pumpkin, and put it back together. I'm thinking if we're going to have the pumpkin apart, this would also be the time to check/change rear drive ratio. Need to look into this more, but if anyone has already thought through the right rear end gearing for a 10 speed Crown, let's talk.

Thanks,

Adam

[dwsmitha]

Originally Posted by upbeat

Hello All,



Update on this thread - had the clutch brake adjusted by a pro. It moved the clutch release point into a "normal" position from the strange position it had been 1" from the top of the pedal travel, but the clutch brake still doesn't slow it down in neutral. A little deceptive since it shifts from neutral fine cold, but once warmed up there's no way not to grind into first, no matter how long you sit with the clutch in.



So it's back in the shop for a second try adjusting the clutch brake.



While we were in we found the differential (aka pumpkin) bolts were a little loose and leaking. Mechanic suggests we drop the shaft, re-pack the pumpkin, and put it back together. I'm thinking if we're going to have the pumpkin apart, this would also be the time to check/change rear drive ratio. Need to look into this more, but if anyone has already thought through the right rear end gearing for a 10 speed Crown, let's talk.



Thanks,



Adam

Adam- Our tandem is an'87 with a BigCam and 350 HP+. We can get away with 4.11s with that much HP & Torque. With a 250 Cummins, I'd really suggest you seriously consider mid-4s in the pumpkin and an RTO-IF you don't plan lots of mountain driving (as the RTO has a 6-1 1st-the RT has an 8-1), and it will give you the economy on the flatlands. If you plan to do hill/mountain driving with a 10 speed and 250, consider mid 4s in the pumpkin and an RT. Otherwise you'll not likely get over 4-5 gear in the mountains pulling grade without heating your engine. Your experience may vary [emoji849][emoji15][emoji106].
Deanna


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[upbeat]

ok... update on the clutch is I had it adjusted by the mechanic at the tireshop, J and O in Oakland. Nice guys. Idea is to do this work myself because wrenching is meditation, but a friend wants to borrow the bus for his wedding, so I'm pushing essentials through at J and O.

Speaking of tires, I got quotes for Kumhos at around 290 a piece - but I drove out on some brand new Michelins for the front. Disposed of the front left, which was scalloped something horrible. Rotated the front right to the back and disposed out of the cap that was rear, inside left. Replaced a worn nipple, and everything looks good. I love restoring old machines. And I love good tires.

But back to the clutch. Had a the mechanic take a look at it and he adjusted it to speck. Short story is the clutch brake still wasn't working. Strange is it's fine to shift cold, but once things warm up it's impossible to get out of neutral without grinding. I talked to the mechanic on the phone and he said he'd give it another look when I brought it back in to take care of the rear brakes.

What's the story with the brakes? Well, they're nearly back together, but before I share that I'm going to go try a build thread and see how that goes.

[Tango]

If that left front was scalloped badly, I would certainly want to find out why before those shiny new Michelin$ get the same way. Could be a number of things but I would definitely check the shocks and maybe the wheel bearing for wear before too long.

[dan-fox]

Originally Posted by Tango

If that left front was scalloped badly, I would certainly want to find out why before those shiny new Michelin$ get the same way. Could be a number of things but I would definitely check the shocks and maybe the wheel bearing for wear before too long.

Tie rod ends? Do buses even have tie rod ends?