u-joint temp?

Status
Not open for further replies.
Joined
Jun 5, 2003
Messages
27,888
Location
Apple Valley, California
i picked up some moly grease for my grease gun. its mainly for my u-joints.reading the www i read that the joints can hit 350f! i find that hard to believe.
but the grease is rated to 290f

worry or not?
 
Shoot them with your temp gun a few times to get a baseline. Doubt if your temps are running that high. I use Moly grease from Tractor Supply for everything including drive shafts. I expect you will be fine.
 
I would think that u-joints running at that high of a temp must be really close to the exhaust system. Are your u-joints close to the exhaust?
 
U-joints might heat up pretty good if the vehicle is under high constant load like from hauling or towing a lot of weight around. I wouldn't think 350 deg F though, unless the exhaust system also added heat as mentioned above.
 
Angularity and RPM are the temperature raisers. Can see how OEMs stucture Universals, and Cardan's to minimise angularity, so that they

stock-ish ride height, and you've got nothing to worry about.
 
http://www2.dana.com/pdf/DSSM-3264.pdf

• Use a good quality E.P. (extreme pressure) grease (Timken Test Load - 50 lbs. / 23 kg. minimum)
• Meets N.L.G.I. (National Lubricating Grease Institute) Grade 2 specifications
• Operating range of +325° F to -10° F (163° C to -23° C)

For u-joint application, I've been using Mystik JT-6 Hi-Temp (red tube) for quite some time now. Carries M-2006-J approval and retails for $3.97/tube at your local WalMart.
 
U-Joint Temp. - I never thought of that.
Comparing front & rear may tell you of a future problem.

Question: When buying u-joints, would you get the zerkless (and not worry about greasing) or with zerks ? ? ?

Types of Greases always confuses me.
Time will tell if I'm using the correct stuff.
For my u-joints, I use:

Lucas ...... Sold at Home Depot
X-TRA Heavy Duty Grease (Green Colored)
NLGI #2 ...... GC-LB
* High Temp. 560 degree dropping Point
* High Speed Bearings
 
Last edited:
Originally Posted By: larryinnewyork
Types of Greases always confuses me.
Time will tell if I'm using the correct stuff.
For my u-joints, I use:

Lucas ...... Sold at Home Depot
X-TRA Heavy Duty Grease (Green Colored)
NLGI #2 ...... GC-LB
* High Temp. 560 degree dropping Point
* High Speed Bearings


http://lucasoil.com/images/documents/TDS_XtraHDGrease.pdf

Dropping point is actually 500°F.

Take a look at the Mystik JT-6 info:
http://docs.mystiklubes.com/msds_pi/M20026.pdf

Dropping point of 550°F. However, service temperature is 325°F.

Lucas doesn't list that specification, but one can extrapolate from what's available that it wouldn't achieve Dana approval due to lack of sufficiently high operating range.
 
The u-joints are my truck are difficult to grease.
I can never get a good seal and end up wasting a lot of grease.

I worry about grease compatibility.
That's why when I take my truck in for its Yearly Inspection,
I also take 'my' grease gun and ask them to grease u-joints.
 
Originally Posted By: Chris142
if given a choice id go with sealed ones. this greasing them is for the birds. especially in my jeep as i must remove theshaft to get to the zerks


Why does it have to be removed? I have to get the shaft aligned a certain way, but I'm able to grease my Cardan joint and all 3 u joints on my rear shaft.

Front shaft ... I just press apart and repack by hand. Some day I'll change it to greaseables.
 
Originally Posted By: Miller88
Originally Posted By: Chris142
if given a choice id go with sealed ones. this greasing them is for the birds. especially in my jeep as i must remove theshaft to get to the zerks


Why does it have to be removed? I have to get the shaft aligned a certain way, but I'm able to grease my Cardan joint and all 3 u joints on my rear shaft.

Front shaft ... I just press apart and repack by hand. Some day I'll change it to greaseables.
the zerks in my front driveshaft point at the yokes.no matter which direction you put them in you cant get to them.i must remove the trans mount\skidpate then unbolt the cardian from the transfer case so that i can turn it far enough to get my needle on the zerks.
 
For the difficult to reach u-joints, many are now available with one of the caps drilled and an almost flush grease fitting installed in it. They require a needle to grease, but work well in tight applications.
 
Originally Posted By: Chris142
if given a choice id go with sealed ones. this greasing them is for the birds. especially in my jeep as i must remove theshaft to get to the zerks


Same here, but sadly, my rear combo joint (1310 size on shaft, 1344/GM 3R on pinion yoke), is not, nor was ever made in a solid joint.

I MUST use a needle point fitting to get any grease into this joint, as a regular, over the whole zerk fitting type will NEVER fit in there, regardless of the driveshaft angle.
frown.gif


Generally, the solid joints are also considered much stronger, by virtue of them not being partially hollow (to accept the grease from a zerk fitting).
 
Originally Posted By: Miller88
Most sealed joints I have bought are all drilled for grease passages, they just lack the tap for a zerk fitting.


Which brands?? All of them?
 
Nope. I used sealed joints in the old Suburban. They had a small divot or reservoir in each trunnion, but they definitely were not drilled all the way through. I believe they were Spicer, and Chevron EP grease was recommended. Mystic JT6 Hi Temp specs are almost identical to the Chevron grease and is easy to get at Walmart. I use the Mystic now on everything (just about).
 
Status
Not open for further replies.
Back
Top