Risk of overpacking driveshaft with grease

Read what Spicer has to say about greasing your driveline
http://www2.dana.com/pdf/J3299-2-DSSP.PDF

 

we do, and your drive shaft has u-joints. your front drive axles have cv joints. ftr and I never seen a zerk on a sealed bearing.

 

Whoops it says on here that it should be done every three months. I should get on that.

 

Thank you OP. I found this thread to be rather entertaining.

 

Just

just adds extra rust protection for you yankees

 

Good ideal to do it after a water crossing to also, forces the water out.

 

Exact document I got that info from

 

X2

 

Now that is a very very interesting explanation.
So according to Spicer, to pack the U-joint evenly with grease, one must be able to "wiggle" the shaft left and right .
So this means no tension on the rear axle.

So in other words, to grease the driveshaft 3 rear zerks correctly, at least one rear wheel must be lifted off the ground and free spinning.

 

Thanks for all the help guys that worked great. BTW I used Harbor Freight pistol grip grease gun filled with Valvoline NGLI2 Synpower and it worked great. With the flexible hose I was able to reach the second zerk on the front shaft without taking the shield off.

 

I hope you don't do your own oil changes......

 

They are needle roller bearings there are gaps between them if you see grease coming out it's lubed. I worked for Dodge in the 60's and they had a service procedure that involved removing the Ujoint greasing them and putting it all back together so be thankful you have fittings. Pretty much every Ujoint that can be subjected to deep water has fittings or if they don't they should the seals are good about keeping grease in but not real keeping water out.

 

Interesting. So if you live in an area with lots of rain yet never submerge the U-joints, realistically, does the road splashing wash out the grease out of the U-joints much?

 

Grease repels moisture, so there is not much concern about water washing grease out of the assembly. The concern is that water will get splashed up inside the bearing caps in the u-joint, then cause rust, which will speed up wear inside the needle bearings and caps.

 

With sealed bearings there is usually a zerk to fill the area between the inner shaft and outer shaft. Not directly connected to the sealed bearing but right next to it. I have them all over at my job. We also have sealed bearing supporting 100 tons tho, they are huge bearings

 

I'd be more worried about accidentally filling your gas tank with 10W-40 rather than water from the roadway splashing grease out of a u-joint.

 

we do understand the difference, but the problem is no one is thinking about sealed bearings
or anything to do with them when the subject is zerks on the prop shaft components

the only problem with over greasing a driveshaft is, if you have a zerk on a slip-yoke,
and you blow to much grease in the slip-yoke, it can cause bad 'hammer' if you drive
and hit a hard bump immediately, it cannot push the grease out fast enough.

so u-joints and double-cardan, pump till it comes out
slip-yoke, pump a few squirts and stop

my taco doesn't have a greaseable slip yoke, my 4runner does

--you must use moly for slip yokes--, moly is optional on u-joints, and
moly won't hurt them whatsoever. moly -is- needed for the slipyoke

 

does anyone know which years they stopped using grease able u joints? My 2015 does not have any zerk fittings on the drift shafts at all.

 

Look harder, seems silly to have non greasable u joints.
Drive shaft wont have the zerks the u joints will

 

I know that the drift shaft doesn't have zerk fittings. I have worked in a garage for quite a while and have changed lots of u joints. I just found it odd that my truck doesnt have any. Its a 2015 TRD DCLB 4x4