Mobil 1 synthetic grease nlgi no 2 (2 Viewers)

[hankinid]

Here is one for you guys to freak on...What if you pumped a ton of Mobil 1 synthetic #2 into the (rear) slip yoke, saw the expansion happening and then saw grease coming out of the u-joint? Nothing came out near the shiny part that appeared. Did I break something or is this another area where the grease can escape?

Btw, the procedure worked as intended with the front and rear u-joints for the rear drive shaft.

BTDT

Looks like a vent or bleed hole drilled into the rear driveshaft on center. I pumped the hell out of mine, saw grease coming out the vent, and stuck my thumb over the bleed hole...couldn't block the flow and I had no grease coming out the front seal.

Waited a week, tried again, same issue. Picked up a seal at local Toy dealer, yanked the shaft, pulled the driveshaft apart and cleaned everything. Installed the new seal and relubed...perfect.

Mine's an '01 LX. No vent on the front driveshaft.

For the poster with the question if FSM talks about lubing the shafts on or off a lift...it doesn't specify. But it doesn't mention lifting in general in the repair section, other than lift point info. I lube mine on the ground, ahc on 'high'. I let it set for a while and lower back to normal.

Steve

 

[goped]

I greased my drivelines however I didn't bleed it out aggressively, worried about damaging the seal. I still have the thud, only when I'm coasting and I step on the gas quickly. Is this a transmission problem? Should I raise the truck and then grease? Any help is appreciated.

 

[pfran42]

Update: Pumped some more grease into the problem drive shaft and a little of the old stuff started seeping out of the slip joint, then the new grease came out again from the u-joint. If I finally get the grease to start flowing freely again from the slip joint, do I still need to tear apart my prop shaft? Is this escape hole built-in or a sign that the seal is completely shot?

 

[Mxndrnks]

I dont have an escape hole on my 2000. And I just pulled both shafts, rebuilt, striped old factory finish and refinished them.....hmmm....

 

[pfran42]

I dont have an escape hole on my 2000. And I just pulled both shafts, rebuilt, striped old factory finish and refinished them.....hmmm....

Thats just it, not sure if it is, in fact, a "breather". Is the driveshaft splined into the u-joint? If so, I can see high pressure grease making it's way out that route.

 

[Mxndrnks]

Gotta picture of what you are looking at? On mine the male side of the slip yoke is splined and the female side has internal spline that match up....

 

[Phx99Cruiser]

Some success...

So right after driving home from work today (100 degrees today) I got under the LC and did my third hit of pumping moly grease into the rear slip yoke zerk. FINALLY got grease pushing out of about half (the diameter) of the drive shaft - only half. But still some success!

Two questions:
1. any idea how I can force grease pushed out of ALL around the seal?
2. do I need to do the same for the FRONT slip yoke zerk?

I did remove the plastic "skid" plate and pump another 20 into the front but no push out yet. I'm unsure if I should continue pumping more into the front as I don't know if it's supposed to push out like the rear.

Thanks!

 

[NMuzj100]

Front should purge the same. The front does not have near as much movement so it tends not to generate "thunk".

Slow migration of oil from the new grease into the junk blocking the seals is what is needed. Come back to the front in a month or so. Same for the half of the rear seal still blocked.

 

[studawg]

Out of all the threads I have read on driveline thunk/noise, I think this one has the most pertinent info. Although, the title of it may prevent some who are researching this topic to find it. I think it should be in the stickies/FAQ. Thanks NMuzj100

 

[hankinid]

This an update on my post at the top of page 2, commenting on pfran42's post...

Was under the LX yesterday to grease shafts and u-joints. Front was perfect, with grease exuding 360 around the splined shaft.

Rear began leaking again at the diff (tubular shaft side) rear end. I pulled the rear shaft and noted that there is a metal disc (I'd call it a welch plug) at the end of the tubular shaft. It appears that the disc/plug is staked in, and that's where the grease leaks once a bit of pressure builds up.

Plan to fix...

Remove male/front shaft. Remove the seal from the front of the female shaft. Remove the u-joint. Remove the plug. Hot-tank the rear side, and brush any residue out (I have a few brass brushes from www.brownells.com originally designed to clean grenade launchers). Silver-braze the plug back onto the shaft. And reassemble in reverse order.

Comments??

Steve

 

[thetimmer]

Thats just it, not sure if it is, in fact, a "breather". Is the driveshaft splined into the u-joint? If so, I can see high pressure grease making it's way out that route.

PFRAN I am having the exact same issue. Did you ever figure out what it is?

 

[2001LC]

Some will see a little hole in back plate of shaft, welch plug as @hankinid called it. This hole was drill mainly by Lexus Dealers shops and some Toyota shop did this as well. It came about because they grew tried of replace drive shaft. Unofficially this fix came from the factory. It relieves pressure in cavity.

Other find grease escaping around the welch plug. This happen because pressure built so high in the camber, that it warp the welch plug plate.

Many have speculated on why this happens, popular belief was dry seals. But that would not explain why brand new (5, 10 or 20K miles) 100's had the clunk and seals would not allow grease to pass.

Bottom line Toyota uses unbelievable good rubber (except vacuum lines,, LOL) throughout the 100's. The seals are just so tight they don't allow passage of anything. With a little grease on them even air has difficult passing. I've torn-down a propeller shaft at 100K miles cleaned and primed seal with #1 grease and still no passage. The seals are so good they're bad. I've also seen them at 200k, 250K & 300K ungreased, worn & cracked with out a hint of clunk, as greased easily passed seals. But not great for water crossing or sand.

It's believed we get the clunk for two reasons. One: Stiction - Wikipedia from inadequate lube. Two: pressure build up in cavity due to tight seal.

Pumping grease in with wheels on ground is best practice, as it keeps rear propeller shaft in neutral position. Pump full when propeller shafts are fully extended, then hit the bumps while driving is risky. Where I've not seen a report directly attributed to excess pressure on drivetrain. One only need hook up a pneumatic grease gun and watch the extension build pressure, pushing yoke and shaft apart. I've observed rear differential all the way up to engine mounts move. Then imagine the force of a road bump at speed. I Liken it to a 200 # man standing, he's 100#'s on each foot, how much more at a run 200#, 300# even more on each. This is common reason welch plug warps producing leak, not all bad as it relieves pressure.

OP suggested of using thinner grease like #1, #0 or even #00, is a good one. This works well to get grease to pass seals, once flowing you can step up to #2 over time in the heat of summer is best. Additionally he recommends cleaning and priming outer rim of seal. This is excellent advise. Once cleaned & primed, I found great trick recently to aid flowing of grease past seals. I learned to pulse grease in while wheels on ground. By this I mean pump in grease until yoke start to extend, build a little pressure. Then give an addition pump so it moves out just a little more and hold. You'll see it start to collapse. As it collapses give a little pump expanding again. Keep repeating, without getting overly extended. This can take minutes and may even need to be over time, possible days or even weeks. The pulse primes the seal from the backside. But eventually grease will pass or welch plug will give. Either way pressure will be relived, shaft lubed and clunk gone.

Edited, Oct 2018: In the 200 series FSM Toyota is now recommending pumping in grease until extension of slide yoke begins and then just stop pumping. This is Safe way to do the job.

 

[Parbo]

just bought a lc. It had the clunk so decided to grease the propellor shafts today. I saw the shaft move about 1cm before old grease apeared from the seal. But not all around. Only about half of the seal was oozing grease. Is this normal? An also i think the drive shaft was put the other way arround? The part in the picture is the rear drive shaft on the transfer case site. That is not good right?

 

[Parbo]

I just bought a 2002 lc 100. It had the clunk so decided to grease the propellor shafts today. The shaft extended 1 cm before grease came out the seals. But not al around, only about half. The picture shows the rear drive shaft connected to the transfer case. I am pretty sure that the drive shaft was put on the other way arround by the previous owner. Am i right?

 

[2001LC]

Grease passing "only about half" is ok, all the way around is best but rarely happens. Older seals especially those that haven't been greased much, tend to be looser allowing grease to flow easily.

Yes that's in backwards. May have small effect on seal, as water or sand would push into seal lip as opposed pass over.

BTW; Welcome to mud, and you can delete your duplicate post.

 

[pjess50]

A bit of a dissertation ....



Not quite.

- When you grease the slip yoke you should pump grease until new grease comes out of the seal. (Per FSM)
- It will usually be proceeded by some water emulsified dirty grease getting pushed out and then followed by the fresh new grease.
- This needs to be done every three thousand miles! or more often in severe conditions. Severe is stop and go and towing, not just outback travel.
- The manual recommends daily if you do any water crossings.
- This is because the grease in the slip is consumed and contaminated as the slip joint does it's thing (slip). Grease is deposited in the area of travel and then is lost to exposure on extension . Dirt/water on the shaft is pushed into the grease and seal on compression.
- Grease also seeps. The lubricating oil separates from the thickeners and flows out of the shaft to evaporate. So it must be renewed often.

This is what you want to see ...
Front drive shaft showing new Moly grease (shiny purple) pushing out old Amsoil 2000 series grease (red). If the old grease was contaminated or emulsified with water this flushing action would be more important.

Clean new grease spilling past the grease seal on the rear yoke. This is what you are after.

Here is the problem and area of controversy.

- Lots of trucks are not greased nearly enough because quick change places and shops hardly bother to grease now that so many cars lack lube points and oil change intervals are often 7500 miles. (Plus, it's dirty under there)
- When not lubed often enough the seal gets dried and caked with dirt to the point that it no longer allows a flow of grease.
- When new grease is pumped into the yoke it extends the shaft slightly rather than pushing old grease out.
- Some have been concerned that filling the yoke with uncompressable grease will prevent the slip yoke from compressing properly transmitting shock to the drivetrain.
- They therefore recommend only shooting in a pump or two of grease.

My thoughts -

- Too much grease is not the problem. A malfunctioning seal is the problem. Fix the problem.
- If the seal isn't working because its been under lubed in the past then purposefully under lubing it into the future is not the right answer.
- Without a flow, grease is not getting to the contact parts that need lubrication.
- A poorly lubricated slip yoke is also likely to transmit forces in excess of the design. (Thunk!)
- If no old grease is coming out and at each lube you place two pumps in it. Then you are just going slower to the dreaded Hydro-locking situation. (There may be some benefit as the lubricating oil separates from it's thickeners and migrates where it's needed.)
- Get a grease gun ($10), a flex hose for the gun ($5) and some grease ($2-5) and do it yourself. Otherwise you'll never know if it was done right.

What to do -

- First try to pump until old grease flows out of the seal area (where the slip happens).
- If you get a little extension don't sweat it. Keep pumping.
- If you can no longer get grease into the zirk and no old grease has left the seal then your's is blocked and needs to be unblocked.
- If you know it's blocked then fix it.

Ideas to free a blocked seal.-

- Pump some NGLI #1,0, or 00 weight grease into the shaft and let it sit. (these are basically the same grease only with fewer thickeners and could loosen the crud at the seal as the lubricating oil migrates). After establishing flow lube with a NGLI #2.
- Heat the shaft gently with a hair dryer ect.. to improve flow. (not trying to cook the oil, just heat it to a flow.)
- Clean the shaft of rust and dirt. Emory cloth ect...
- Jack the truck up to full extension, pump full with grease and lower slowly to put a lot of pressure on the clogged seal.
- Clean with a little solvent.
- Remove the driveshaft, take apart and clean. Reassemble and grease.

Other notes - Watch for grease compatibility. Just about any grease will do for this application but some don't work well together. Lithium thickened greases may not work well with some marine greases.

I use a Amsoil Synthetic EP Lithium NGLI #2 with 3% moly (it's purple). Mobile 1 #2 should work well although those who have studied such things say that it trends thick for a #2.

If you hear or feel some "thunk", grease it again.

I know this is an old thread and maybe everyone knows this but I didn't really understand. I had the "clunk" on my new to me 1998 LC. I followed these recommendations and now it's smooth as butter. I think it's important to note the FSM recommendations of doing this every 3000 miles. Just felt like this was an excellent description of an important topic.

 

[2001LC]

I just bought a 2002 lc 100. It had the clunk so decided to grease the propellor shafts today. The shaft extended 1 cm before grease came out the seals. But not al around, only about half. The picture shows the rear drive shaft connected to the transfer case. I am pretty sure that the drive shaft was put on the other way arround by the previous owner. Am i right?
View attachment 1357713

Grease passing "only about half" is ok, all the way around is best but rarely happens. Older seals especially those that haven't been greased much, tend to be looser allowing grease to flow easily.

Yes that's in backwards. May have small effect on seal, as water or sand would push into seal lip as opposed pass over.

BTW; Welcome to mud, and you can delete your duplicate post.

I wrongly stated your propeller shaft was on backward. I've since learned Toyota at some point turn the propeller shaft around, so that slip yoke is nearest the transfer case. My 01 is nearest the rear differential. So it's likely 2002 was the year they changed, since you have an 02.

 

[abuck99]

My 05 FSM has the slip joints facing the diff's- however I run the opposite- slip joints towards Tcase.

Im not sure it makes any difference which direction their mounted.

 

[2001LC]

Now you've got me looking @abuck99

07 FSM has yoke both ways: FSM MA-9 to Transfer, FSM PA-9 to diff.
01, 04 & 05 FSM have MA & PA to Diff.

On my 06 & 07 yoke s both to transfer.

On my LX & LC's 98,00 & 01's all yoke's to diff.

 

[tjb]

I pumped grease in today - 150,000 miles.

Old grease came out of the spider yoke seals.

No grease came out of the slip yoke seals and the shaft didn't extend. Instead, it started coming back out the zerk.

My shaft looked like it might have already been extended - there was a shiny area at the ends. Sorry for the quality of this picture, but arrow is to the shiny area:

I ended up using nearly a whole tube of grease. The good news is that a squeak seems to have gone away.

Any thoughts on this, and what I should do next?