Modified Tail Shafts, how to measure up?

[stradlater]

I'm going to get a single piece tailshaft from the back of the a340 to the hilux diff.

2 questions

A) What's the process for measuring it up and then taking it to the tail shaft place to get made up correctly? Which bits do I need to measure?

B) I have a tailshaft at the moment which won't fit, but has the correct fittings on either end. I'm actually hoping to keep that tail shaft in one piece and then use replacement fittings on the end of the new tailshaft. Are these the sort of things they buy new as replacement items or do you basically have to source second hand ones?

[merc-blue]

OK WELL,

A)
The easiest way to measure it up is center-center of the unis,
Each time i have had to build a tail shaft its from scrach so i ordered the unis, gearbox shaft and diff flange, assembled the unis into there respective ends, put the respective ends into the gearbox and bolted to the diff, measure the distance
Make soure your trailing arms for the diff are parrallell to the ground when you measure it all depending on how the trailing arms are setup it can affect the length,
Also allow for the slip join (im assuming gearbox ouput) is not all the way in and has appropriate engagement
B)
You can sorce unis and the tail shaft ends, you will probly be able to get the diff flange new aswell, the gearbox output may be hard to get new.

Hope this helps

[stradlater]

So by the sound of things, it's better just to use the old shaft fittings?

[merc-blue]

Depends on the load, Idealy new gear is better,
But the existing flanges with new unis would surfice.

[stradlater]

where do I order them?

[The Real Roadrunner]

diff flange to gearbox seal measurement and any decent tailshaft supplier should be able to build it from that measurement, make sure you tell them the correct PCD on the diff flange coz while there is only 1 spigot size on toyotas there are about 5 different pcd's, what box are you running? you will need the spline count and size + seal id.

cheers
linden

[TheStitt]

I've always done the same as what Roadruner has done. Gear Box seal to Diff flange. I have also taken in what bolts to the diff flange. As well as the yoke for the back of the box.

Gear box place has always been able to supply new and or upgradded uni's etc

[Joshstix]

From http://www.sydneydriveline.com/car_measure.htm

http://www.sydneydriveline.com/shaft_measure_long.gif

[too_quick]

I measured from the diff flange to the gearbox oil seal. Driveline services made it up and it was exactly the right length. Cost me $270 from memory for new uni's and a new shaft.

[stradlater]

on an a340, how do I see where the gearbox oil seal is? I've got a cover thing over the yoke.

[The Real Roadrunner]

generally you will need to knock the cover off if using big aftermarket uni's like a 1350 series spicer, it's only there to stop salt from japanese roads etc.

just do it with a tape measure straight in the back but be sure to miss the output shaft as they protrude 10-15mm out the back of the seal.

cheers
linden

[shelldrake]

I took a bit of a guess with mine...could see the wear mark from with old tail from gear box. measured from end of flange to this mark with new box in position.calculated difference in what i had to what i needed *about 30mm. took to tailshaft shop - made the shaft longer (and compatible with gearbox output) for $250(nice...). worked perfecly so far.

I havent actually had the car in question runnig yet, but it doesnt seem to be an issue when I jack diff up all the way and then drop to full droop...

Should also mention that this cover roadrunner mentioned was previously taken off mine already, so it was a little easier to measure. :)

[stradlater]

Perhaps you should come measure mine up Shelldrake. ;-)

[shelldrake]

Can do, if you are stuck - No responsibilty will be taken if s@#t gets f%$ked up from a poorly measured tailshaft. :rolleyes:

[jet81j]

kind of stealing this thread but whats the tolerance on your measurement, like can you be out by a few mm.

[shelldrake]

If you are asking me that q - I was using the stock tailshaft as a reference - Provided you don't bottom out at any point and there is still as close to the original amount of tailshaft over theoutput shaft from gbox, you would assume this to be acceptable - But perhaps ring a driveshaft shop for a more accurate tolerance for specific applications.

[The Real Roadrunner]

you should have the shaft set up so it has 15mm minimum that it can slide further into the box but if it IRS it wont matter as mauch do to the fact that the diff wont move.

cheers
linden