Mobil 1 synthetic grease nlgi no 2 (6 Viewers)

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i was wondering if its okay to use the Mobil 1 Synthetic Grease NLGI NO 2 for driveshafts? is it okay to mix synthetic with the regular NLG1 NO 2 non synthetic? How many grease points are there? How would i know if i've put enough grease already?

THANKS...
 
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You're fine to mix synth and dino. I think there's a zerk on each u-joint and one near the slip joint. Somewhere I read that people just pump grease in until you see it coming out the splines. But contrary to that I've also heard that you shouldn't do that because if you compress the DS quickly and the slip joint space is full of grease, it will slap against it and could cause problems.
 
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You're fine to mix synth and dino. I think there's a zerk on each u-joint and one near the slip joint. Somewhere I read that people just pump grease in until you see it coming out the splines. But contrary to that I've also heard that you shouldn't do that because if you compress the DS quickly and the slip joint space is full of grease, it will slap against it and could cause problems.

so, how much grease should i pump in it?
 
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I just researched this on here and there are several posts regarding this, but I did not find a single post that had the entire answer so I will post up here. FYI, I researched this as I have never had a slip yoke that had a zirk fitting, and thought hmmmm.... this has the potential to cause a serious problem. So here goes:

Yes dino and synth can be mixed. (Although they don't actually "mix") And Yes the Mobil 1 NLGI 2 can be used.

The u-joints can be lubed using the zirk fittings by pumping new grease in until old grease comes out. If you want to get all of the old grease out (which you will if you are switching to Mobil 1) you can pump grease in until the new stuff comes out (Mobil 1 is red and original is blackish). You will then have all synth in your u-joints.

The slip yoke is a different story. if too much is put in there is the possibility of causing damage, as indicated by Trunk. The issue comes about because grease does not compress, what happens is that the yoke moves during suspension travel and when you lube the driveshaft you typically do not have it at full compression. This means that there needs to be space left for movement of the yoke on full compression (or the most compression it will have).

The quick way is to pump some grease in, probably about as much as you put into the u-joints when the original grease started coming out. Then to be safe back the zirk fitting all the way out and go for a drive and try to get full compression of the suspension. If there is too much grease it will come out through the open hole. Clean this up and reinsert the zirk fittings.

The not so quick way is to take the propeller shaft off and relube making sure to leave the cavity for compression as mentioned earlier. If you are going to do this it will be easier to lube the u-joints while they are off the truck as well.

A couple of notes:
1. It has been said that the new grease will not get past the old grease when lubing the slip yoke. I have not opened mine up yet, but most likely this is true.

2. The area of the slip yoke that is silver is the area that is traveled on during drive line movement. So if there is rust on a section of the slip yoke it does not compress that far. To be on the safe side you should allow a cavity big enough for some compression onto the rusted area of the yoke (I believe Toyota has a spec for lubing the slip yoke in the FSM).

3. If you do a lot of water crossings, or putting a boat in and out of the water you will most likely have lost grease and your propeller shaft parts will probably be quite dry.

4. Even if you are not taking the drive shaft off it is a good idea to re-torque the propeller shaft bolts. This is recomended service by Toyota, and from some of the posts on here it seems like this is for a reason (typical of Toyota to have a reason :p).

5. A quick mention as to why too much grease in the slip yoke is bad. If the slip yolk can not compress then it will put the weight of the truck into the transfer case and differentials. Taking the weight of the truck is what the suspension/bumpstops were designed for… let them do their job!

And if anyone thinks that letting the drivetrain take the abuse that was meant for the bumpstops is a good idea imagine this. Jack the truck up to full extension, fill the slip yokes completely full, then go jump the truck. Ouch!! I guarantee that the bumpstops WILL work better. :clap:
OK, so that is it. I hope that covers all of your basic questions on lubing the propeller shaft and u-joints. :cheers:
 
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A bit of a dissertation ....

.... The slip yolk is a different story....

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.

attachment.php


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

attachment.php


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.
 
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I don't disagree with the "pump until you see new grease" thought, but only under certain circumstances. If you've got the truck on a lift and the slip yoke is extended, there's a lot of room in that cavity to pump in grease. If the truck on the ground, then the slip yoke is already partly compressed, so when it extends there's space available.

My concern with pumping until you fill it is that grease can't escape past the seal under compression fast enough. It's designed to let it ooze out, not shoot out when the DS suddenly compresses. Given with on road or mild trail driving, it's unlikely that the DS would compress like that.
 
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i went to Autozone just now.. i did find MOBIL 1 SYNTHETIC GREASE and it's RED, but it doesn't say NLGI 2!!! other brands say NO 2.. i want to use MOBIL 1..
 
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Trunk - I deffinately agree with you as far as not having on a lift while filling slip yoke.

NMuzj100, informative post. I still need to get my FSM :eek:, does it say anything else as far as how to grease the propeller shaft? IE leave on ground (not on lift), or how to remove excess grease?

Also, you said that lots of trucks are not greased properly. I might say that in NA that most trucks fall in this category. A lot of guys on here purchased their 100s used, typically this means that the lubing of the propeller shaft was not done properly and the seal is not working properly. IMO the best thing is to take it apart clean and relube, then you can lube per FSM. Knowing that mine had 70K on the clock when I bought it and it most likely had never been lubed I am not risking the damage and until I take apart have not filled per your post. Once I get it cleaned and lubed then I can do the proper maintenance. (although 1 to 2 pumps IMO would not be near enough for first time especially)
 
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My concern with pumping until you fill it is that grease can't escape past the seal under compression fast enough. It's designed to let it ooze out, not shoot out when the DS suddenly compresses.

The slip yoke system should allow the grease to flow easily. If it does not "ooze" the old grease out as fast as you can pump it in then your seal is not working right. If you don't fill it then no new grease gets to the parts that need lube and you have not pushed out the old "used up" and contaminated grease. Rapid compression should not displace much grease and if you have a established a proper flow then it will have a pressure outlet.

I think the concerns about drivetrain damage due to overgreasing aren't supported by any evidence while the very common "thunk" comes from too little lube and obviously has forces associated with it that you can feel in the cab.

IMO the best thing is to take it apart clean and relube, then you can lube per FSM. Knowing that mine had 70K on the clock when I bought it and it most likely had never been lubed I am not risking the damage and until I take apart have not filled per your post. Once I get it cleaned and lubed then I can do the proper maintenance.

I think taking it apart before you know if you have a problem is probably overkill. Try and fill and see if you have a problem first. If your seal is blocked and you feel uncomfortable driving with the grease inside then remove the zirk, go for a spin and then seal it back up.

does it say anything else as far as how to grease the propeller shaft? IE leave on ground (not on lift), or how to remove excess grease?

No. It has a diagram showing the four lube points and says to use "Multi-Purpose Grease".

attachment.php
 
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Rear driveshaft removal question

After reading these discussions about driveline greasing, I took some 5% moly Amsoil grease to all of the fittings. On the rear slide yoke fitting I stopped after about 20 pumps and it seemed like the shaft was moving - no grease came out of the slide. This morning after having driven it around for a week I pumped several more strokes in and again watch the shaft make a slight sound and move some. Still no grease coming out of the shaft as some others pictures show. I removed the zirk and jumped up and down on the rear bumper to relieve some pressure - about a 2" stream of grease came out.

I'm feeling like I need to remove the rear driveshaft. My question is do I just remove the four bolts where it connects to the rear diff, or ???

Pictures of the area:
101_0301.jpg
101_0302.jpg
 
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Pump more! The sound and movement are good. Pump it until the shaft raises at least an inch or so. Clean the area where the yoke slides with a mild solvent (I like WD40) or even a penetrating oil like PB blaster.

Then I'd drive it but you could just let it sit a few hours and then pull the zerk again since it sounds like you have hydrolock concerns. Keeping that grease under pressure should push the oil into the junk.

Give it a few more weeks to allow the oil in the new grease to seep into the old dried up grease and make it pumpable.

Until you get flow you could try using a #1 or #0 grease. It has a greater oil/thickener ratio so more oil to seep into the accumulated junk.
 
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Then I'd drive it but you could just let it sit a few hours and then pull the zerk again since it sounds like you have hydrolock concerns.

I've read a lot about people worried they may cause a rear drive shaft to hydrolock if they over lube the slip yoke.


How many, if any, forum members have experienced this problem? On Land Cruisers, Tacomas or otherwise?
 
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I've read a lot about people worried they may cause a rear drive shaft to hydrolock if they over lube the slip yoke.


How many, if any, forum members have experienced this problem? On Land Cruisers, Tacomas or otherwise?

BTT. Anybody ever experienced hydrolock?
 
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I don't think it's possible. The grease will find it's way out down the splines if enough pressure is created. It's just the old gunky stuff that's blocking it from flowing freely.
 
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I switched from the Mobil 1 synthetic grease to the Valvoline Dura Blend. Its a Moly Blend synthetic that seems to do a nice job. The M1 stuff does not have Moly in it.

As far as the slip yoke goes, I had to pump it a few different times over a number of weeks to get it fully greased, I would stop pumping because didn't like the amount of presumed pressure build up. It didn't appear that my drive shafts had been greased every 5k and I had a small amount of clunk. Its all good now and I don't feel the need to pump till it squeezes past the seal every time and wouldn't unless I was driving through lots of water on a regular basis.
 
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Its all good now and I don't feel the need to pump till it squeezes past the seal every time and wouldn't unless I was driving through lots of water on a regular basis.

It you don't purge past the seal when greasing you are slowly filling the grease channels with oilless thickeners (Lithium soap actually looks like a soap without the oil in it). You are also not clearing the seal area of infiltrated water and grime.

Purge it. If you are only using a few pumps at each greasing you'll probably end up having the grease separate out in your gun and be worthless in a few years anyway.

Good call on the Valvoline Grease. One of the most cost effective solutions for the slip yoke.
 
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Verification for both rear AND front slip yokes

This discussion about pushing grease out past the seal of the slip yoke, grease point(s) #2 on the diagram someone posted, is this true for BOTH the rear and front zerks?

I've been concentrating on the rear and don't want to neglect the front! :eek:
 
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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.
 

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