slspacek Posted March 8, 2013 Share Posted March 8, 2013 I am replacing an input shaft on the pump transmission of my 1966 C-95 Mack fire engine. I had to remove the short drive shaft between the 5 speed and the pump tranny. I figured while it was out I might as well service the u joints on that shaft. I have the origional manual that came with the truck and it states that these joint should be lubricated with straight 90 weight gear oil and following that statement in the manual are the words ( in caps) DO NOT USE GREASE. These U joints are the ones with two bolts and a football shaped cap on each side of the cross holding the bearings in and on those caps are the words Spicer and use oil. Any one know why use oil versus grease? The crosses in the U loints have a grease gun type fitting on them as stated in the manual and apparently also a relief valve in case of high pressure. Next question, do they make a tool/pump that will fill these joints with the gear oil through the fitting? Any help or recommendations would be a huge help. I may replace the u joints while they are out, any suggestions on what to replace with? Thanks fellas. Keep on truckin.Sean Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/ Share on other sites More sharing options...
slpwlker Posted March 8, 2013 Share Posted March 8, 2013 Thats a new one on me Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-170489 Share on other sites More sharing options...
39 Baby Mack Posted March 8, 2013 Share Posted March 8, 2013 SeanJust grease them.If your going to replace them take them apart and take themto the truck parts house to have them matched up.just off the top of my head sounds like a 1710 series Spicer.Ron Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-170492 Share on other sites More sharing options...
rsb502 Posted March 8, 2013 Share Posted March 8, 2013 I was always told it was due to the speed of that shaft under pump load, I have a pump to put oil in grease fittings, got it at NAPA. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-170565 Share on other sites More sharing options...
steamer Posted March 9, 2013 Share Posted March 9, 2013 Hi Sean I have a 1938 American lafrance that I had to put bearings in the pump transmission a number of years ago it has spicer u joints and axel and calls for oil in the u joints it has regular grease fittings on the crosses I have been using grease in them with no problems. I don't put a lot of miles on it either Dean Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-170857 Share on other sites More sharing options...
slspacek Posted March 16, 2013 Author Share Posted March 16, 2013 Thanks guys, I am going to replace the joints on the shaft due to the fact that on each end there was 1 bolt completly missing and the others were not very tight. Could have been some vibration there. Upon inspection of the other drive shaft from pump to rear wheels, there is oil/grease being slung from two of the caps. I will be replacing those as well. while the rig is down for the season this is the time to do it. Any advice on getting those U joints appart? Pretty sure they are the origionals from 1966. Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-172409 Share on other sites More sharing options...
felicello122 Posted March 16, 2013 Share Posted March 16, 2013 Thanks guys, I am going to replace the joints on the shaft due to the fact that on each end there was 1 bolt completly missing and the others were not very tight. Could have been some vibration there. Upon inspection of the other drive shaft from pump to rear wheels, there is oil/grease being slung from two of the caps. I will be replacing those as well. while the rig is down for the season this is the time to do it. Any advice on getting those U joints appart? Pretty sure they are the origionals from 1966.Hammer time! Can use a press if available. Little heat if neccesary. Quote Link to comment https://www.bigmacktrucks.com/topic/30328-spicer-u-joint-lubrication/#findComment-172477 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.