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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jun 2008 Posts: 37 Apprentice | | Apprentice Joined: Jun 2008 Posts: 37 | OK - I am a total "virgin" when it comes to these dump trucks. And these are going to sound like dumb-@ s s questions but I'm a big guy and can take the flogging  When I bought the truck the owner "assured" me the dump worked perfectly but needed fluid in the piston or resevoir. I've read on this forum the procedures to fill the lift cylinder either exteneded first or pumping it in with the bed down - I'm hoping for the later option  Deal is...once I check/fill the lift cylinder... Q. What the heck do I do to get the bed to go up and down doh! And where does the PTO come in?Q. Can someone please describe shifting the 2-speed rear end?Q. Is the transmission be synchronized or do I need to double-clutch? I only ask because it doesn't want to down shift from 3rd to 2nd and am curious if that's an indication of a problem? Upshifting seems to be fine.BTW - If I could find an operators/owners manual I might not need to ask such dumb questions  | | | | | Joined: Apr 2003 Posts: 942 'Bolter | | 'Bolter Joined: Apr 2003 Posts: 942 | Just ask away.
Some answers:
1) There is a PTO knob that should be obvious somewhere within the drivers reach. Push in the clutch, pull out the PTO and slowly let out the clutch.
2) We have detailed info on 2-Speed shifting here on the board. Try a simple search and see if it will produce. Let us know if you can't locate it.
3) Your trans should be synchronized. What actually is happening when you downshift?
Bill
'60-'72 Chev/GMC Fan GMC 9500 Fan Detroit Diesel Fan
| | | | | Joined: Jun 2008 Posts: 37 Apprentice | | Apprentice Joined: Jun 2008 Posts: 37 | <[censored] to second = maybe going too fast?
Bill - Thanks for the quick reply!
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | Even though the transmission is synchronized, double clutching, and revving the engine near the rpm's you will be at after the shift will produce a much smoother shift. I started driving in the days when transmissions were spur gears and you had to double clutch. It takes some practice, but you will feel much more professional if you can shift smoothly. First gear is not synchronized and it will grind if you don't double clutch or put it in when you are standing still. | | | | | Joined: Jun 2008 Posts: 37 Apprentice | | Apprentice Joined: Jun 2008 Posts: 37 | Even though the transmission is synchronized, double clutching, and revving the engine near the rpm's you will be at after the shift will produce a much smoother shift. I started driving in the days when transmissions were spur gears and you had to double clutch. It takes some practice, but you will feel much more professional if you can shift smoothly. First gear is not synchronized and it will grind if you don't double clutch or put it in when you are standing still. Thanks I'll try paying attention to the rpm and shift points next time I take it out - my grandpa, rest his soul, was a commercial truck driver. I remember many hay haulers and other trucks on the farm and watching my grandpa double clutch driving those rigs like it was nothing. | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | Nice truck! Really nice tires, did they come with the truck?
Bruce | | | | | Joined: Apr 2003 Posts: 942 'Bolter | | 'Bolter Joined: Apr 2003 Posts: 942 | You may also have a bad or worn synchro and double clutching, as mentioned above, will produce a smooth shift. Just make sure the clutch is all the way out when you hesitate in neutral when bringing up the RPM's before you downshift to a lower gear.
Bill
'60-'72 Chev/GMC Fan GMC 9500 Fan Detroit Diesel Fan
| | | | | Joined: Jun 2008 Posts: 37 Apprentice | | Apprentice Joined: Jun 2008 Posts: 37 | Nice truck! Really nice tires, did they come with the truck?
Bruce Thanks Bruce, the C50's a 25ft'r to be sure but the tires on the front are Bridgestone 22.5 radials and the rears are Goodyear rock-lug recaps with less than 500 miles on them and is one of the reasons I bought the truck - the side walls don't even have a scuff in them! I've been hearing that tire prices are about to take a huge jump in retail pricing - nearly double current prices if rumors are true. :mad: I put 1200 bucks worth of rubber on my crew-cab dually 4 months ago - I can't imagine them going up double :mad: or what new tires on a big rig would run :mad::mad: | | | | | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | I don't think your question about the PTO operation was fully explained or so it seems to me. As mentioned, engage the PTO with the transmission in neutral. Then work the pump valve lever or control back and forth slowly. If there is sufficient hydraulic oil in the cylinder it should begin to raise and lower as you work the control in/out or back and forth. DON'T forget to disengage the PTO before you drive the truck or you could have a mess on your hands and some ruined parts. NEVER reach inside the frame with the box raised to work the control valve on the pump. The box can drop like a shot and you will die! I cannot stress this enough. Safety is always first.
Last edited by 53moneypit; 06/16/2008 4:17 AM.
| | | | | Joined: Jun 2008 Posts: 12 New Guy | | New Guy Joined: Jun 2008 Posts: 12 | Not sure if you found the 2spd rear end shifter. On older models, it was typically mechanical shifted by a lever and rods to the back axle from the driver seat on lower left seat end (for my old '40s models). From what I remember, only light duty trucks had the vacuum actuated 2spd optional rear end control. I beleave they were on the dash. So maybe the newewr ones moved to vacuum control by the 60s but I am not 100% sue.
Otherwise, everything described above is good to get you going. I too learned to drive in them old '30s and '40s w/ compound gears and had to do a lot of shifty foot work to down shift on hills and was easy to float them gears though and save you cluytch and brakes when you really got to know your truck and let her talk to you. because when you let the girl talk, she can tell you so much just by listening to the winding of the gears and vacuum of the engine. | | | | | Joined: Sep 2008 Posts: 24 Apprentice | | Apprentice Joined: Sep 2008 Posts: 24 | A little late on this topic but This may help or help some one. Somthing I was working on I was planing on printing it as a sticker. 2 speed sticker instructions Brian | | | | | Joined: Jan 2008 Posts: 77 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2008 Posts: 77 | If it is a vaccum shifted rearend, when you get ready to shift, put the speed selector where you want it, let off the gas, wait a second or two, then step on the gas-- voila-- shifted. | | |
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