Ok, I finally got this completed, thanks to everyone's help. I have a 2008 Sport Edition V6 4Runner, and I used the 2007 Repair Manual PDF from the Toyota website.
If anyone is inept at propeller shaft lubrication as I am (was), here is a quick break down.
What you need:
14oz Grease Gun w/ Flexible Hose (sometimes you have to buy flexible hose separately) and Nipple Attachment for application to Zerks
14oz tube of Mobile 1 Synthetic (or equivalent)
Something to prop your vehicle up with like a heavy duty floor jack
Some blocks or jack stands
rag or towel
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The biggest thing I was concerned about, with this operation:
1. accessibility to the underside of the vehicle
2. not overfilling the Sliding Yoke type of zerks
Be aware there are 3 types of Zerks. What the hell is a zerk you ask? Well, I didn't know either, but looked it up: A zerk fitting is used to lubricate mechanical parts that require grease. A zerk fitting is also called a grease fitting.
The 2 types of zerks on the 4runner are:
Propeller Shaft Slider
Propeller Shaft Sliding Yoke
Total amount of zerks that need lubricating: 6 (3 zerks per shaft)
[Please Note: the PDF from the 2007 Repair Manual is a bit confusing, as it shows a diagram for some other type of vehicle which doesn't match what I was seeing under my 4Runner. You might only have to refer to the top diagram, which shows only 2 zerks.]
Link to PDF from Repair Manual
The particular type of zerk that you need to be extra cautious with is the 'Sliding Yoke'. As others have stated above, it can be a bad thing if you shoot to much grease into this zerk.
Now that you're informed, you'll need to lift the vehicle, to create some room underneath. You can lift the vehicle however you are comfortable. Be aware that on the 4WD model, you can freely rotate (by hand) the front propeller shaft, but the back propeller shaft will not rotate, unless the rear wheels are off the ground.
I used the curb and one ramp (see image below) for this operation. It worked for me (i'm 6'2" about 175) but I can slide/fit into the most tiny areas without a problem. Probably not the most efficient way, but this method of ramp+curb was certainly the cheapest that I could find at the house. I don't have a jack, nor do I have jack-stands.
This meant that I would not be able to hand turn the rear propeller shaft but that turned out to be ok. There is plenty of room above the end of the shaft (where the zerks are located), that I could reach up and around to the top of the shaft without a problem.
As I mentioned earlier, there are 3 zerks on each propeller shaft. On the front propeller shaft, there is 1 (one) zerk on the front of the shaft that faces towards front of vehcile and 2 (two) zerks on the rear.
On the rear propeller shaft, there are 2 (two) zerks on the front of the shaft that faces towards front of vehicle and 1 (one) zerk on the rear.
That makes for a total of 6 (six) zerks that need lubrication. Again, be careful with the zerks that are identified as the 'Sliding Yoke' types. You do not want to overfill these, as they can cause problems with your vehicle operation.
For me, I performed this operation at 23,000 miles. I should have performed it at 10,000 miles as indicated by the scheduled maintenance guide that came with my vehicle. But I am comfortable that no damage has been caused.
1. I started with the rear propeller shaft and slid under my vehicle from the rear, under the bumper. I placed some towels on the ground to keep my shirt clean and just crawled under there with the grease gun. Because I could not rotate the rear shaft (rear wheels were on the ground) I had to reach up and locate the zerks, as they happened to be turned facing upward (towards sky) and away from me. They were easy to locate with my hand. I cleaned each nozzle with a rag, then pressed the grease gun nozzle onto the zerk. Then I pumped the grease gun several times (see blow for exact amounts).
2. For the front propeller shaft, I moved the towels and accessed the underside from the driver side of the vehicle. The shaft is easier to reach from the drivers side. I did the same thing here. Located the zerks, cleaned them off with a rag, then applied some grease.
Rear of the Rear Shaft:
zerk 1 - (slider) - 3 squeezes of trigger
Front of the Rear Shaft
zerk 2 - (slider) - 3 squeezes of trigger
zerk 3 - (sliding yoke) - 2 squeezes of trigger
Rear of the Front Shaft:
zerk 4 - (slider) - 3 squeezes of trigger
zerk 5 - (sliding yoke) - 3 squeezes of trigger
Front of Front Shaft:
zerk 6 - (slider) 2.5 squeezes of trigger
[Please Note: The squeeze amounts are what was required for my vehicle. The amount of lubrication your vehicle requires may vary quite a bit, and it depends on the type of grease gun you are using as well.]
