Non plunging 930 rear drive project.

[dsrace]

i don't remember from seeing it in person but in the pic it looks like it's pointed at the shaft. now after riding with him and knowing he's 1/2 to wot ALL the time lol i bet he is cranking some heat out at that axle and knowing that at that elevation the boiling point it lowered i can see it. not that much grease in there to begin so def need the best and higher temp grease he can find.

[fabr]

Still skeptical. Personal opinion is failure was due to lack of lube,not temperature.  I'll bet 99% of failed uj's are due to improper lubing or bad cup seals.

[fabr]

Install method can be a big issue as well. How many of us press the cups in instead of grabbing a big ol' hammer? I threw the hammer install method in the trash a long time ago. Ditto for disassembly. Put the thing in the press.

[dsrace]

the hotter they get the faster the grease wants to run out and i have had enough experience with neapco to know they are not up to the task on motor cycle powered sand rail or 3.8 v6 powered either lol  they a poor design compared to spicer or rockford imo based on my application. i modified a very large c clamp years ago so not to use a hammer and the vise when ever possible.

[dsrace]

now given this is a truck chart and not sandrail chart but principal is the same imo and is why i asked what rpm you were running at and hp/tq of that motor when you were able to hold 2nd gear all day.

http://www.southwestpowersports.com/gearchange.html

[fabr]

If the seals are good the grease cannot do any thing other than lube the joint. Still cannot see the temp of the uj going past the operating range of quality/proper lube. We all know I am not in favor of uj axles but on the other hand I cannot see the operating temp being a factor in failure. It is much more likely the large and constant angular change is to blame or just using whatever grease is in the grease gun......

[dsrace]

interesting video and always grease till it comes out of all 4 caps that i thought was just common knowledge lol when i ran them i would grease them before every trip and wipe off the excess of course and on a week trip i would grease them again say wens evening or afternoon depending. but these practices were probably over kill however i would get many seasons w/o issue with the good u joints like rockford or spicer. i do have to say out of all the brands i tried neapco is the bottom of the barrel and that one really surprised back then since they were still made in the usa where the precisions weren't at that time.

[dsrace]

If the seals are good the grease cannot do any thing other than lube the joint. Still cannot see the temp of the uj going past the operating range of quality/proper lube. We all know I am not in favor of uj axles but on the other hand I cannot see the operating temp being a factor in failure. It is much more likely the large and constant angular change is to blame or just using whatever grease is in the grease gun......

the brand is a huge part of the issue which will acct for seal failure. neapco and the cheaper ones had what always felt like hard plastic seals and they would crack easy.

[fabr]

Most lubes are good to 325F ,some synthetics are good to over 550F. I stand by my position that it is not a temperature related failure. Cheap components,improper lube methods,improper install and run of the mill lube are most likely culprits. Temperature is not the issue,IMO unless you are building some serious heat but I seriously doubt the axles were ever going over 300 degrees.

[fabr]

interesting video and always grease till it comes out of all 4 caps that i thought was just common knowledge lol when i ran them i would grease them before every trip and wipe off the excess of course and on a week trip i would grease them again say wens evening or afternoon depending. but these practices were probably over kill however i would get many seasons w/o issue with the good u joints like rockford or spicer. i do have to say out of all the brands i tried neapco is the bottom of the barrel and that one really surprised back then since they were still made in the usa where the precisions weren't at that time.

I'll bet a c note that 99% of all uj's lubed are done incorrectly and only partial lube is achieved. I'd also bet that most "techs" will NOT replace a uj because one or more trunions will not purge.

[dsrace]

agreed

with a cracked seal and a lot of heat i can see them wearing very fast especially the neapco. enemy has several years on his rockford u joints behind his turbo busa running 1100 paddles. given jersdunz is soooo close to st a ( lucky sob lol )that he see's a lot more run time.

[fabr]

The " lot of heat " thing is all speculation since it was not measured and even too hot to touch would likely be well within operating temps....................wellllllll,you can see my skepticism. IF the temp of the uj's was taken and is/was above 300F then I'll back off my assertion.

[jersdunz]

The " lot of heat " thing is all speculation since it was not measured and even too hot to touch would likely be well within operating temps....................wellllllll,you can see my skepticism. IF the temp of the uj's was taken and is/was above 300F then I'll back off my assertion.

The " lot of heat " thing is all speculation since it was not measured and even too hot to touch would likely be well within operating temps....................wellllllll,you can see my skepticism. IF the temp of the uj's was taken and is/was above 300F then I'll back off my assertion.

I see your point.
Watching this video... You posted I bet it's a lube issue. I was running conversion joints and they never purge equally..

[fabr]

the hotter they get the faster the grease wants to run out and i have had enough experience with neapco to know they are not up to the task on motor cycle powered sand rail or 3.8 v6 powered either lol  they a poor design compared to spicer or rockford imo based on my application. i modified a very large c clamp years ago so not to use a hammer and the vise when ever possible.

many times the ears are deformed/misaligned/bugged up during disassembly.Very few ,myself included,have proper fixtures for removal of a u-joint. Years ago I attended the Spicer/Dana driveline school in Cincinnatti. They teach the proper way to do things and I can tell us this much; we don't usually do it that way. :lol:

[jersdunz]

OL Brian had to throw more options in my direction.. He has some goodies from an old build that he had to tempt me with..
Here is the question to spacer or not to spacer..  left side is with @ 40d and the right side is without @ 40d ...



Damnit i'm liking the side with the spacer.