Building My Overland Tacoma: Plans, Progress, Perplexions

[maxama10]

Not saying this will work, it has solved many peoples problems though, the 1 piece tom-woods driveshaft.

From what I read it worked for most, but not all.


I gathered this info from Toyotanation

 

[Overland Hadley]

Not saying this will work, it has solved many peoples problems though, the 1 piece tom-woods driveshaft.

From what I read it worked for most, but not all.


I gathered this info from Toyotanation

Thanks for the info.
A new drive shaft sounds expensive.

 

[Overland Hadley]

Something that isn't often mentioned is that the plane of greatest angles needs to be considered and that both ends be in the same plane, but that this plane is not required to have any particular orientation relative to the ground or chassis centerline.

Ignore for the moment that there are UJ's in the mix and just think of a piece of wire with a bend in it. The plane that the entire wire lays in is the plane that I'm referring to.

Now think of the wire with two bends in it. They must not be bent such that the entire wire can't lay in one plane, but there is no requirement for how this plane is oriented relative to the Earth.

Measuring with a level only gets you so far. If there is any lateral offset in the vehicle (extreme example: centered output transfercase used with an offset output intended axle) then those angles need to be measured as well. The plane of the most extreme angle can then be determined for each end individually and checked that they are co-planar.

I suspect that this is why sometimes what "shouldn't work", does. And what "should work", doesn't. Even though the angles relative to horizontal have been measured, it isn't the total picture.

Works on some vehicles and not others, sounds like I need to just start throwing parts at it and see what works.

 

[slooowr6]

I think what ntsqd meant is some did make sure the two UJs are parallel to each other BUT did not make sure they are on the same plane. Some happen to be on the same plane so no vibration some are not on the same plane so they feel vibration. Maybe before spend $ check if they are on the same plane.

 

[ntsqd]

I think what ntsqd meant is some did make sure the two UJs are parallel to each other BUT did not make sure they are on the same plane. Some happen to be on the same plane so no vibration some are not on the same plane so they feel vibration. Maybe before spend $ check if they are on the same plane.

Thank you! This is a hard thing to put into words. As checked with a level the angles can be the same, but the plane of the actual max angularity (which is not always perpendicular to the ground) may not be the same at both ends of the shaft.

Depending on the length required, a one piece driveshaft be be significantly more. There is a ratio of diameter to length that can not be exceeded or you'll learn what vibration is really all about. For a short while anyway, then the shaft will do something ugly.

If you do opt for a new driveshaft make sure that they use Toyota and not Spicer flanges. There is a Spicer flange made to fit Toyotas. I was told that these use a U-Joint that is not as strong as the Toyota part and is not able to operate at as high a max angularity as the Toyota part.

 

[keezer36]

BUT did not make sure they are on the same plane.

I'm not sure what is meant by "the same plane", I'm assuming parallel between the output and input yolks vertically. Or are you also referring to a left/right orientation?

I had this vibration problem but never fully understood it in that why it was particular to '05+ Tacomas and...well not all vehicles in that the way I understood it so far was that torque took the u-joints out of parallel causing the rear one to wobble.

I had a stock vibration at take off and after a 1.75" lift in the back, more so. I placed 1/16" flat bar spacers under the carrier bearing mount for a total of 3/16" which gets me very close to harmony. One more eliminates the take off vibe but then induces a vibe at about 50mph which I do believe is the most common issue of one-piece drive shaft owners.

"Math is Hard" -Barbie

 

[ntsqd]

I'm not sure what is meant by "the same plane", I'm assuming parallel between the output and input yolks vertically. Or are you also referring to a left/right orientation?

To find the accute angle you need both the up/down and the left/right angles. If the vertical angles match AND the horizontal angles match (or are of equal value but opposite sign), then the accute angles will also match and the accute angles are in the same plane. Just having the 4 measurements is good enough unless you're driven to do math-stuff.

Unfortunately, the horizontal angle is not so easily measured. And that is where I think the variation in action vs. results comes from.

We should all just go back to torque tubes like the Model T's had (just slightly ahead of Mogs). All of these trials would go away......

 

[slooowr6]

Let's try with a picture.

ntsqd,
Thanks for sharing the knowledge!
Let's try use the xyz 3d coordinate system on the above picture. Z = top to bottom, X = left to right, Y = front to back. The picture is for Z axis, the setup rule when looking from the side of the drivetrain. What you meant is the same setup rule applies to Y axis as well right? Which means the picture will be what you see looking straight down on the drive train from above. In most case it should look like a straight line. But in case they are not in straight line it should be in phase just like the vertical setup.
Did I confuse everyone enough?

 

[ntsqd]

Take that middle picture and assume that it is the top view rather than the side view. Those top view angles are just as important as the side view angles, yet because they are hard to measure, few actually measure them. Most assume that there are no angles in the top view and for the most part that is probably true. But not always true.

It's the not always true that can bite you. The engine may not actually be centered on the pinion shaft. As viewed from the top it may not even sit in the frame parallel to the chassis centerline.

 

[keezer36]

So by placing a correct number of spacers under the carrier so that both shafts share the same angle of depression, it gives the individual a little more breathing room before he exceeds the four degree limit.

The X axis thing is interesting. I would assume any tolerance for deviation would be approaching zero.
And mine and many others (perhaps all) of these '05+ Tacomas are not level in the front left to right. I know when I put on the adjustable coilovers, I left the 3/8" difference left to right in the front simply because I did not understand why it was there.

I'm probably clutching at straws here but if the rear suspension is level but the front is not, does this not change the square of the frame creating a deviation in the X axis?

I'm unemployed and my bank account is approaching zero. Sounds like a good cheap test to run this afternoon.

 

[slooowr6]

Take that middle picture and assume that it is the top view rather than the side view. Those top view angles are just as important as the side view angles, yet because they are hard to measure, few actually measure them. Most assume that there are no angles in the top view and for the most part that is probably true. But not always true.

It's the not always true that can bite you. The engine may not actually be centered on the pinion shaft. As viewed from the top it may not even sit in the frame parallel to the chassis centerline.

Finally got it!
Overland Hadley, Sorry to hijack your build thread.

 

[Overland Hadley]

Finally got it!
Overland Hadley, Sorry to hijack your build thread.

No problem at all. This is all part of the build.

 

[Overland Hadley]

So would installing alignment shims at the rear leaf springs be the best thing to try first?

 

[slooowr6]

Finally found a pic on the web from http://www.drivetrain.com/driveline_angle_problem.html.
2 phase drivetrain set up. View from side and top.

1 phase drivetrain set up. View from side and top. This should be the type of set up for Tacoma, Tacoma has a carrier in the middle but still the same type of set up. The drive line should be straight looking from top. If there is a kink then there will be vibration.

I would go get an angle finder like this one, http://www.lmperformance.com/6564/8.html, and see how is the current number. Then go from there.

 

[ntsqd]

You can get that angle finder from a local hardware store.