The OFFICIAL clunk/thunk driveshaft thread (3 Viewers)

[lexi4darin]

Hard to imagine that the hole is by design. My hole was not center, not smooth, and had rough edges. Of course, it's impossible to get grease into the drive shaft / yoke cavity and have any grease get to the front seal with a hole this large in the back of the drive shaft (u-joint side).

 

[natharmstrong88]

Sorry if someone has already brought this up, but I didnt have time to read through the whole thread before I went to work. But the way we fixed the clunk when I was working as at the local Toyota dealership here in town, was to pull the shaft off, seperate the slip yoke and file down the ridges that had developed along the splines. The reason given from toyota that the splines has developed the ridges was that it was due to poor machining, and the wrong type of grease being used from brand new.

So if you file the splines, then use moly grease after its all cleaned out and back together, you shouldnt have a drama.

 

[Gunney]

I ended up putting too much grease in the props and developed a fast vibration at 120kmph, i will be pulling the grease nipple off tomorrow and separating one side of the prop to remove some of the grease.

 

[lexi4darin]

natharmstrong88 - did Toyota/Lexus ever design a hole in the back of the drive shaft? Maybe to act as a way to release pressure when the driveshaft is compressed. ?

 

[NMuzj100]

A hole of this type, although usually of a smaller diameter, is used by some other manufacturers like Dana Corp to allow for pressure relief in cold weather on some of their driveshafts. In the Dana lubrication manual linked earlier in this thread they recommend covering the hole with a finger tip while lubricating the drive-shaft.

I bet the previous owner drilled that hole after reading a bunch of "scare" threads in the 80s section about how excess lube was going to blow his transmission into the rear of the engine damaging both.

I ended up putting too much grease in the props and developed a fast vibration at 120kmph, i will be pulling the grease nipple off tomorrow and separating one side of the prop to remove some of the grease.

No such thing as too much grease in this system. It's designed to be filled with grease until it purges past the seal. I would look elsewhere for the cause of the vibration.

 

[RobRed]

NMuzj100 What brands of grease do you recommend. Be specific please, i dont want to think about it.

 

[SR.GRINGO]

nmuzj100 what brands of grease do you recommend. Be specific please, i dont want to think about it.

amsoil has many flavors.

 

[bamabrock]

I use the Mobile 1 Moly grease

 

[NMuzj100]

NMuzj100 What brands of grease do you recommend. Be specific please, i dont want to think about it.

From post #54 in this thread - This grease has a Aluminum Complex thickener and is compatible with Lithium greases.

And this is the stuff I'll be using next ...

Schaeffer Lubricants | Supreme Moly Grease

A little hard to find when buying less than a case. I was nearly eaten by a guard dog at the truck depot I bought mine at. I'll report back when it's field tested.

I was using Amsoil EP HD #2 with success but it is discontinued. Their Tech Services recommended AMSOIL Synthetic Polymeric Off-Road Grease (GPOR2)
(NLGI #2 - 5% Moly) I'm not sure if this grease will be "pumpable" enough for the 100 driveshaft but I'm sure it'll be tough enough. Going to the #1 might be a option. This grease's Calcium Sulfonate thickener is compatible with Lithium complex greases.

SL3330 -- Moly-Graph® Extreme Pressure Multi-Purpose Lithium Grease Reports are that this Sta-Lube grease works well and it's very inexpensive.

Valvoline SynPower Synthetic Grease should be a good grease with added Moly.

Valvoline - Ford, Lincoln and Mercury vehicles multipurpose grease should be in most parts stores and easy to find.

Valvoline Palladium looks like it would work too

The key is the Moly not the carrier grease.

I use the Mobile 1 Moly grease

Link please. Can't find it.

 

[lexi4darin]

In the Dana lubrication manual linked earlier in this thread they recommend covering the hole with a finger tip while lubricating the drive-shaft.

Makes sense. I tried and failed a few times at plugging the whole with my finger (keep it PG guys!).

I bet the previous owner drilled that hole after reading a bunch of "scare" threads in the 80s section about how excess lube was going to blow his transmission into the rear of the engine damaging both.

I get where you're going but it's doubtful. It's a two owner truck, a Lexus tech who has it for 90k; second owner was a friend of the Lexus tech and a big hot shot mortgage type. Not really the types to be drilling holes or tweaking on their trucks in any unconventional manner.



As for the grease brand and type, I only really focus on the type. I use Graphite Moly Lithium grease. Currently using this one but I don't care for or against the brand.

 

[bkgee]

I use the Mobile 1 Moly grease

Mobil1 grease does not contain moly. But I use it on my drive shafts anyway (too lazy to have two grease guns) and it eliminates the thunk for me just fine.

 

[hankinid]

http://http.cdnlayer.com/ec1images/225/products/9/998016857_090707_vs.bmp[/IMG]SL3330 -- Moly-Graph® Extreme Pressure Multi-Purpose Lithium Grease Reports are that this Sta-Lube grease works well and it's very inexpensive.

It's great stuff. I get mine at the local NAPA store. OT but if you shoot it's great on guns

Steve

 

[natharmstrong88]

natharmstrong88 - did Toyota/Lexus ever design a hole in the back of the drive shaft? Maybe to act as a way to release pressure when the driveshaft is compressed. ?

I don't believe so.

We tried different greases first off as well, but customers would keep coming back after a while, more irate each time, and the filing was the permanent fix, no more complaints after we did that.

 

[spressomon]

I don't believe so.

We tried different greases first off as well, but customers would keep coming back after a while, more irate each time, and the filing was the permanent fix, no more complaints after we did that.

With the clunking getting worse I just pulled my rear driveshaft yoke. No pressure relief hole. When I cycle the two mating parts there is NO pressure venting or relief and an obvious need for pressure relief. And no ridges/wear pattern on the splines.

It just seems logical this part needs to have some type of venting to relieve the pressure that develops when its cycling. The down side is with even a small vent hole at the rear of the yoke it has the propensity to introduce dirt to the splines. Me thinks I'm going to drill a tiny hole and see how it goes...

 

[marcfj60]

Figure out what size hole you need to drill if you want to tap it for a 10-32 screw to be threaded into it. Put the screw in when you grease it. Take the screw out when you're done.


Or if that hole is too big, try a #2 or #4. I would think if the yoke is full of grease to the point that it's oozing passed the seal and out the hole, it's not likely that much dirt or water could get into that hole when the plug is removed.

 

[lexi4darin]

spresso-

I'm with Marcfj60 on that one. The reason my problem persisted the way it did was because of a hole in the end of the yoke. Also, let it be known that I had a hole, essentially a pressure relief system, and I still had the clunking. The clunking has only gone away now that I've plugged the hole and greased it to hell and back.

 

[NMuzj100]

The clunk is caused by the splines "sticking by friction" under rotational pressure and then slamming free rather than smoothly sliding. An extreme pressure grease that plates the surfaces with solid lubricants addresses this issue. Adding a relief hole will not.

If you really want a hole though, I say go for it. I don't think it will help but I doubt it'll hurt either ...

Moab Jeeper Tom Woods Interview

MJ: Your CV seems to be missing that little hole. Why is that?

Tom: Elimination of the center relief hole provides for a positive pressure greasing and ensures the correct flow of lubricant when servicing.

**Engineerees translation: No hole = no grease escape.​

I think finding a Dana/Spicer drive shaft and matching their hole size would be the best idea. I couldn't find the size in my internet searching.

For those who worry about hydraulic locking of the shaft I think drilling a relief is a better solution than under greasing.

 

[spressomon]

Yes the clunk and the positive pressure are two separate issues. I'm always surprised/shocked, how resistant the LC driveshaft yoke is to compression. That certainly can't be beneficial to the t-case output nor the pinion. But then again I'm no Toyota engineer

It also seems, although I really don't have any comparative measurements from Dana/Ford/Dodge/Tom Woods, etc. to support this, the spline to yoke overlap is rather short. Me thinks this might be a contributing factor with our somewhat exclusive clunk. I know the clunk is also a 4R thing. And Toyota is fully aware of the issue. But I've never experienced it with any of my several dozen other vehicles I've owned over the years.

 

[TheFuzz]

Don't have any of the dreaded thunk yet, but I climbed under my rig last week with a grease gun and some moly EP grease from O'Reillys anyway as preventative maintenance. Magically all of the rear driveshaft zerks were pointed straight down. How's that for luck?

Got the spiders greased up ok, but didn't get as much into the driveshaft as I had hoped. From what I could see, it looked like the "shiny" area where the two halves meet/slide isn't shiny at all. Very corroded. Should I be concerned about this? I need to pump a ton more grease in there as I didn't even come close to getting enough pumped in, but if I need to pull the driveshaft to have it cleaned up then maybe I should wait. I'll try to get a pic later.

 

[lexi4darin]

I think not having the shiny spot is a sign that your parts need more grease. Mine were not shiny until I greased them.