Greasing Drive Shafts

[Boing]

On u-joints I pump until good clean grease comes out of the joint, however many pumps it takes (for grease either follow FSM or use what you got; anything is better than nothing). The slip yoke is far more critical to the driveshaft as its not as easily replaceable (Yota driveshafts typically put all the zerks in a line when assembled similar to factory, otherwise use prevailing driveshaft phasing logic...). I typically use a grease with high moly content (10% or more) on the slip yokes, pull the slip yoke off and clean the male and female sides, then butter it up with new grease, remove the zerk and push the yoke all the way down, re-install the zerk and be on your way...

I never use the slip zerk to grease it as it just puts the grease above the splines, every driveshaft I have ever taken apart always has unused grease sitting at the top of the cavity which doesn't help the splines at all...

 

[Bogart]

I’ve managed to snap the zirk off of the rear drive shaft slip joint, I can get the stub out of added hole with an easy out. What size zirk are these so I can just but a couple instead of a whole kit?

 

[Dirt Ferguson]

This has been a good discussion and I’ve read numerous threads now on grease selection and timing of lubrication.

I made a bad decision this weekend and bought a grease gun from a chain auto parts store. It did the job, but then the grease gun fitting got stuck on the zerk on both front driveshaft U joint locations and the rear driveshaft U joint zerk closest to the diff. I had to completely disassemble the hose and its fittings to get the zerk fitting off each time. PITA.

I was frustrated so I did some reading and finally bought a Lincoln grease gun and a needle fitting to access the rear driveshaft, front U joint zerk.

My takeaway from all these threads is that maintaining a modest and regimented lubrication routine is key to driveline happiness. Don’t overdo it, but stay on top of it with each oil change. Thanks.

 

[Biota]

I am hoping to put this topic to rest - at least for me - and let my recent odyssey into the world of greasing driveshafts and why it is important give some fastidious owners some peace of mind when greasing their own drive shafts.

I have owned my 80 series for about a year. It has a 2 inch lift and is on 35’s. I had a mechanic check it over before a long trip this last summer. He did an inspection and hit the grease points. I took off on a cross country trip assuming everything was properly greased and it ran great the entire trip. I should add that I only bought this truck 2 years ago and had not had an opportunity to go over everything myself.

This is the important part. In the last month my 80 developed a slight clunk when starting from a stop. After some research in this forum and elsewhere I determined that a good place to begin to fix this clunk was with greasing the drive train. Makes sense that the slip yoke or u joints might bind up a little if they aren’t greased properly. I greased the u joints but I wanted to see how much grease was in the driveshaft. I pulled that apart and it was bone dry.

This is when I went down this rabbit hole of greasing driveshafts and the discrepancy between the service manual and on-line posters warning me of the dire consequences of over-greasing. So I took a measured approach and called in the experts. After calling five land cruiser specific repair shops on the east and west coast and two dealerships - all said to grease until grease begins to come out of the seal around the drive shaft.

At this point, I wanted to do an experiment. So I first just smeared a moly synthetic grease on the splines and put it all back together. This mostly fixed the clunk and I knew I was on the right track. Then I greased the shafts until they just barely moved. This fixed the clunk even better. Totally even.

After looking a bit more at the design of the slip yoke it hit me that the point of greasing at all is to get grease where metal touches metal. To do that I needed to follow the instructions in the service manual and the advice of seven experts who risk replacing a t-case if they mess it up by over-greasing. So I did what they said to do. I will add that after I fully greased the shafts I removed the zerks to release the built up pressure. Which as I write this it hits me that the positive pressure was likely considered by the Toyota engineers who designed this rig to last 25 years in a third world country and is necessary for proper lubrication but I digress.

I apologize for the length of this post but I am going wheeling this weekend and will report back if anything gets damaged due to too much grease.

Thanks for tying up the thread! I'm a novice here and like the grease experiment you did. I have been getting a 'clunk' sound when I put my '97 LX450 into reverse, she's due for an oil change so I'll just add driveshaft greasing to the project.

 

[BILT4ME]

To add to yet another "Lube Your Shaft" thread:

When greasing your drive line, make sure to do this when the drive line is UNLOADED. This does NOT mean the wheels off the ground.
It means:
Wheels chocked
Parking Brake set
Transmission in neutral

This takes off the pressure of the weight of the truck against the wear side of the splines or the caps in the crosses. It allows the grease to flow more freely into the needle bearings and down both sides of the splines in the yoke.

Wipe off the tip of the zerk prior to installing your grease gun. This way you are not injecting dirt and debris into your fresh grease.
I use a "needle tip" permanently mounted on my grease gun.

I use Red-N-Tacky 2 (Lucas) for the U-Joints and Valvoline Palladium (moly fortified) for the slip yokes.
You can make your own decision on brand and type you want to use.
I have two grease guns. One is always loaded with moly and the other is always loaded with R-N-T2.
One GG is a Lisle long handle with an 18" hose and the needle tip permanently mounted for the R-N-T2.
The other is a pistol-grip from Harbor Freight with the moly with a standard tip and hard pipe with the 30° angle (or whatever it is).

 

[FMC80]

To add to yet another "Lube Your Shaft" thread:

When greasing your drive line, make sure to do this when the drive line is UNLOADED. This does NOT mean the wheels off the ground.
It means:
Wheels chocked
Parking Brake set
Transmission in neutral

This takes off the pressure of the weight of the truck against the wear side of the splines or the caps in the crosses. It allows the grease to flow more freely into the needle bearings and down both sides of the splines in the yoke.

Wipe off the tip of the zerk prior to installing your grease gun. This way you are injecting dirt and debris into your fresh grease.
I use a "needle tip" permanently mounted on my grease gun.

I use Red-N-Tacky 2 (Lucas) for the U-Joints and Valvoline Palladium (moly fortified) for the slip yokes.
You can make your own decision on brand and type you want to use.
I have two grease guns. One is always loaded with moly and the other is always loaded with R-N-T2.
One GG is a Lisle long handle with an 18" hose and the needle tip permanently mounted for the R-N-T2.
The other is a pistol-grip from Harbor Freight with the moly with a standard tip and hard pipe with the 30° angle (or whatever it is).

Can you do it with the wheels off the ground without issue though?

 

[BILT4ME]

Can you do it with the wheels off the ground without issue though?

If you want. The hard part is catching them as you go over the jump.......

 

[COYS]

To add to yet another "Lube Your Shaft" thread:

When greasing your drive line, make sure to do this when the drive line is UNLOADED. This does NOT mean the wheels off the ground.
It means:
Wheels chocked
Parking Brake set
Transmission in neutral

This takes off the pressure of the weight of the truck against the wear side of the splines or the caps in the crosses. It allows the grease to flow more freely into the needle bearings and down both sides of the splines in the yoke.

Wipe off the tip of the zerk prior to installing your grease gun. This way you are injecting dirt and debris into your fresh grease.
I use a "needle tip" permanently mounted on my grease gun.

I use Red-N-Tacky 2 (Lucas) for the U-Joints and Valvoline Palladium (moly fortified) for the slip yokes.
You can make your own decision on brand and type you want to use.
I have two grease guns. One is always loaded with moly and the other is always loaded with R-N-T2.
One GG is a Lisle long handle with an 18" hose and the needle tip permanently mounted for the R-N-T2.
The other is a pistol-grip from Harbor Freight with the moly with a standard tip and hard pipe with the 30° angle (or whatever it is).

So very helpful.

Thanks to BILT and @george_tlc, I got this needle fitting at my local O'Reilly's which makes u joint zerk access a breeze. Thanks, gents!

 

[george_tlc]

^ glad to read that you like the needle tip. It certainly removes all frustration of getting to those UJ zerks. That Lincoln tip is the exact same as I use (I mistakenly thought it was the Milton), but the black tip end reminds me it's a Lincoln tip. I also use a Lincoln grease trigger grip grease gun. Life is too short to fight with cheap/junk grease guns

cheers,
george.

 

[slock]

Explain. I am running slee control arms with caster set for a three inch lift along with icon adjustable remote reservoir shocks and ome springs. I have delta pan hard lift and drop brackets for the sway bars. Is there a better lift?

 

[slock]

Sounds like a cheap lift to me!

Explain. I am running slee control arms with caster set for a three inch lift along with icon adjustable remote reservoir shocks and ome springs. I have delta pan hard lift and drop brackets for the sway bars. Is there a better lift?

 

[DIRTBIKEUSA]

Hi, I grease @ oil changes. I use the cheap Walmart tubes most of the time. Several million miles and no problems. Mike

Boom! Best practice!

 

[clx16]

Explain. I am running slee control arms with caster set for a three inch lift along with icon adjustable remote reservoir shocks and ome springs. I have delta pan hard lift and drop brackets for the sway bars. Is there a better lift?

Your lift is good. My statement was a joke as the perceived 1/4im lift one gets from using their drive shaft as a hydraulic cylinder actually can lead to damage at the tc and the pinion due to the fact that it removes the drive shafts ability to slip and adjust to lengths while components flex.

 

[slock]

Your lift is good. My statement was a joke as the perceived 1/4im lift one gets from using their drive shaft as a hydraulic cylinder actually can lead to damage at the tc and the pinion due to the fact that it removes the drive shafts ability to slip and adjust to lengths while components flex.

Roger. I get it now and agree.

 

[pasquinel]

Yep! The splines wear out and the yoke starts to wobble sideways and you get a hell of a vibration. It will smooth out when at highway sped, but as soon as you back out of the throttle, it vibrates hard, then straightens out again as it switches phase from acceleration to deceleration.

I've driven many old rear-wheel drive cars and pickups that have been neglected and worn out (poor farmers) and old Studebakers and Chevy trucks.

Many street-driven cars never have the problem with the slip yoke because they are sold or wrecked before it ever becomes an issue. But when you live on a gravel / dirt road, the dirt gets in there and wears it faster.

During the 80's, some manufacturers experimented with teflon spline coatings to eliminate the need for regular greasing. It worked for autos, but not trucks.

ALWAYS better to grease than NOT grease. Just make sure you do it with the driveline UNLOADED so the grease gets where it NEEDS to be instead of on the opposite side.

Do NOT over-grease it to act like a hydraulic ram because it WILL wreck bearings.

Driveline unloaded: Neutral in T case good enough?

 

[BILT4ME]

Driveline unloaded: Neutral in T case good enough?

Yes. Just make sure you have the wheels chocked and/or parking brake set

 

[Kernal]

I'll toss this in the discussion as I recently installed a new Toyota rear driveshaft (Propeller) in my 97 FZJ80 Series. The original shaft was in good shape but it had a couple of notchy U-joints (poor maintenance early in it's life by the PO) so figured I'd get a new part while it's still available and rebuild the old shaft when needed.

I had intended to pull the slip yolk out and use my own lubricant anyways but was surprised when I got the new shaft apart to find only a very small amount of the same yellow grease that's found in new U-joints. One thought is that the yellow grease may have PTFE in it (? YM-103).

Point is we all know to lube new U-joints (individual or already installed in a new shaft) before running them, but we should also fully lube the slip yolks of a new driveshaft. I'm sure most people on this forum would grease everything on a new driveshaft but I could see where that step might get missed ie: assuming Toyota fully greased the new Propeller shaft at the factory.

This is what I used on the new prop shaft after completely degreasing the splines:

Dupont D-321 dry Moly spray first (because I had it on the shelf) on the splines, wait for it to cure (can speed that up with some heat from a heat gun), then brushed on Loctite LB 8012 Moly lubricant which is 65% Molybdenum Disulfide. For grease I used Mobilith SHC 460 (slip yolk and U-joints) which is a Lithium complex grease with synthetic oil that has a viscosity of 460. It's a NLGI # 1.5 so the grease may feel a tad "thinner" than NLGI #2 but the viscosity of the 460 lubricant oil in the grease is more than double many automotive greases. For those that don't know, adding Molybdenum disulfide to the splines significantly decreases friction and metal-to-metal contact due to the sliding/scuffing type motion they experience.

FWIW I added grease into both the shaft side using a long adapter nozzle and the slip yolk splines/cavity before reinstalling the slip yolk first with the zerk fitting removed, ran the slip yolk all the way in (some grease came out the zerk hole), then installed the shaft into the vehicle and reinstalled the zerk into the slip yolk, then pumped more Mobilith SHC 460 until the shaft just started to move, then went for a short drive, no problems.

Dupont D-321 Dry Moly Aerosol: (need to let it fully cure, see Data Sheet link)

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

https://www.dupont.com/content/dam/Dupont2.0/Products/transportation/Literature/Downloaded-TDS/MOLYKOTE%20D-321%20R%20Anti-Friction%2071-0219E-01.pdf

Loctite LB8012 Moly "paste" lubricant (brush on):

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

FWIW since installing the new driveshaft I've put 5000 miles on that 80 with the above listed lubes in the shaft (Mobilith SHC 460 only for the U-joints, no Moly). No issues including at highway speeds; no vibrations, not slinging excess grease, just the usual small amount around the slip yolk shaft.


Click on the attachment below to check out the specs of the Mobilith SHC 460 grease: note that Mobil refers to it as good for Marine (wet) environments but it has a Lithium complex base so compatible with other Lithium base greases:

 

[tech_dog]

This has been a good discussion and I’ve read numerous threads now on grease selection and timing of lubrication.

I made a bad decision this weekend and bought a grease gun from a chain auto parts store. It did the job, but then the grease gun fitting got stuck on the zerk on both front driveshaft U joint locations and the rear driveshaft U joint zerk closest to the diff. I had to completely disassemble the hose and its fittings to get the zerk fitting off each time. PITA.

I was frustrated so I did some reading and finally bought a Lincoln grease gun and a needle fitting to access the rear driveshaft, front U joint zerk.

My takeaway from all these threads is that maintaining a modest and regimented lubrication routine is key to driveline happiness. Don’t overdo it, but stay on top of it with each oil change. Thanks.

One of my better moves in life was to buy upgraded grease gun zerk couplers, specifically the Milwaukee.

For 30 years I used the "stock" coupler that came with mid-priced grease guns, and thought the connection fight was just part of the deal. I got the Milwaukee, and they go on easy, hold better, and come off much easier than the couplers that came with the 4-5 mid-priced grease guns I've bought in my life.

https://www.amazon.com/dp/B00LCU7I20