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| | | Forums66 Topics128,034 Posts1,055,533 Members48,425 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | My stock 49 three-speed is losing a lot of oil. As I had undergone a seal problem in the past and installed an Okie assembly I know what to look for. My differential is not overfull so the oil does not seem to be going there. It is all over the floor of the garage. I do have a sheet of lino under the engine/trans so it is not affecting the concrete. When I visually check under the truck there is oil on the trans drain plug but that is the lowest point so I cannot see it coming from there. There is oil on the transmission mount and also where the ball housing joins the torque tube at the collar. I have the impression it is coming from the gasket area where the ball housing joins the transmission. When I did the Okie install I used 4 gasket/shims at that joint to obtain the right amount of play (as per the shop manual). On my 53 the PO had just used a Permatex type of gasket former instead of the shims. I am thinking if I remove the existing shims I may do the same. That is all I can think of so if any 'bolter has any ideas please pass them on. Thanks | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | I recently found an oil leak using UV oil dye and a UV flashlight. If you pin point the source of the leak you can get a better idea of what to do about it. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Good tip, thank you. Years back when I rebuilt the trans there was a slight crack in the case and I patched it with JB Weld. Might have cracked again, it has been 12 years. When I fill the trans I use a mixture of Quaker State trans oil and Lucas supplement which is supposed to prevent/stop leaks. Ever since I feel the leaking has increased although the Lucas rep I saw at a trade show claims it should not make things worse. | | | | | Joined: Jun 2012 Posts: 1,747 'Bolter | | 'Bolter Joined: Jun 2012 Posts: 1,747 | The most common leak over time is the compression seal on the ball to torque tube. It must slide and often the torque tube is dirty or rough at the contact area. With the shims and no sealer the ball can be taken apart(most of the time) with out damage. then the trunnion removed. Drop the torque tube(I use a floor jack to control and lift the tube). Pull the seal compression joint apart, look for any distortion to the seal(it is just cork). Slide the ball off, clean the tube and look for sharp spots that can cut the cork. Reassemble with a light coat of gear oil(on the tube. Snug it all back and keep the compression joint tight( I check mine in the spring and the fall, it is always a little loose). That should help. Channel lock pliers work and a pig pipe wrench will too. Just don't crush the Knurled part and distort it.
Steve H
| | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Thank you. I was hoping not to disassemble the torque tube but may have to. When I got my gasket kit for the ball housing the cork seal was rubber. Bevelled. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Just re-reading your post and checked my gasket collection. I have a set of Fel-Pro for the ball housing and it includes a large and small rubber gasket for the collar and where the ball housing bolts to the trans. There is also a thin flat steel ring which I presume holds the smaller gasket/seal in place. At first read I thought I would have to undo the u-joint but realize I can remove it with the splined shaft attached. Or do I have to take apart the u-joint? Been many years since I did my Okie assembly and my memory is not what it was. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Seems the leak is mainly at the knurled collar. Its not a big job to fix it but hate the idea of doing it lying on my back. The other question is will I have to dismantle the u-joint to get the shaft out? | | | | | Joined: Jun 2012 Posts: 1,747 'Bolter | | 'Bolter Joined: Jun 2012 Posts: 1,747 | Try just snugging that knurled collar a bit. They do work loose. If that helps, you are good to go. If the seal is damaged, you will have to pull it apart to replace it. No a bad job, about an afternoon on a carpet under the truck. Bit messy but not a lot of work. Use a floor jack to support that torque tube, it is heavy.
Steve H
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Seems the leak is mainly at the knurled collar. Its not a big job to fix it but hate the idea of doing it lying on my back. The other question is will I have to dismantle the u-joint to get the shaft out? Yes - unless you want to: - lift the rear of truck a little bit off the ground and put jack stands under the rear frame - support the rear end under the "pumpkin" with a floor jack - disconnect the rear end from the springs - lower the rend end so the wheels are on the ground - roll the torque-tube assembly backwards (supporting the torque-tube so it does not drop down when it clears the joint yoke and bell/cover) This is not a joke, I have done it, after reading the procedure in an old shop manual. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | The knurled collar is snug to the point if I twist it by hand the whole unit twists. Was hoping for a miracle regarding the u-joint. I know that when I put the Okie assembly in I had removed the shaft and dismantled the u-joint but was wondering if it was for some other reason. My concern is the small head bolts that hold the u-joint together. Is there a replacement for them? I know small head cap screws would work but there is no means to keep them from twisting out. Maybe I will give that collar a slight turn using a pipe wrench but am awae of damaging the o-ring. Mine was rubber not cork. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | My concern is the small head bolts that hold the u-joint together. Is there a replacement for them? I know small head cap screws would work but there is no means to keep them from twisting out. Use a locking clip under each pair of bolts. | | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | I understand that and have used them but the stock bolts have smaller heads than most of that size and I was looking for a substitute. Cap screws with their round heads cannot be secured with those clips. When I did the Okie assembly I ordered clips and Grade 8 bolts from a well known supplier in the Pacific Northwest. The holes in the clips were so big the bolt heads went through them. And the Grade 8 bolts? I don't think China understands that standard. These bolts looked like white metal and even had casting marks on the side. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Grade 8 bolts have 6 marks on the head, like a clock face, I believe. They probably sent you the lock tabs for a larger bolt, send back. Driveshaft shops usually have a supply of new bolts.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Dec 2003 Posts: 2,953 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 2,953 | Driveshaft shops. Good point. Never considered that. Thank you. | | |
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