rear end angle

[hennie]

I do a a light vibration in the driveline when I drive car so I guess this could have something to do with the famous angle at the rear end.
When I measure it at the flange of transmission yoke is has a 3 degree angle, at the rearend it is 3 degree as well while the driveshaft itself at the rearend( the last part before the axle measured after the middle bearing where it is mounted to the chassis) measure 6 degrees.
so it has a positive angle at every point I measure it
does this need any adjustment?

Hennie

[Light02atl]

Hennie,

try measuring the angle under the crank pulley, then measure the angle on the rearend flange. Subtract those two numbers and see what you come up with. If I am not mistaken, the number you come up with now is +3degrees. The pinion angle should be no more than +/-2 degrees.

At what speeds do your vibrations occur?

0-25 is usually the pinion angle
65-75 is usually a tire balance issue
throughout all mph, could be tight clutch packs or a fluid issue

I know the 04+ non heritage F150s had a big problem with driveline vibration (regardless of them being a Saleen) at about 68-72mph. There might even be a TSB out there.

Links:
http://www.ford-trucks.com/tsb/tsb.php/m-FORD/d-F-150/y-2007/t-061916

and

http://www.ford-trucks.com/tsb/tsb.php/m-FORD/d-F-150/y-2007/t-07109

[hennie]

It occurs at low speeds, like you stated under 40MPH.
How do I adjust this properly, just loosen the U bolts and place some shims in between and work my way to 1-2 negative degree's?
as it is not like with mustangs to adjust with adjustable trailing arms,...
which makes me wonder, aren't there any better drive shafts available like one pce aluminum driveshafts??

Hennie

[Light02atl]

Hennie,

You want it to be as close to 0 as possible. You are correct though. Once you know if you have an excessive negative or positive angle, you will know which way to slid the shims in. I know SUmmit Racing sells them, they are a little pricey....$50 or so. Once you know what your negative or positive angle is, you will also know what size shim to buy.

As for a one piece driveshaft, I was laughed at when I asked around. However, looking at the saleen charged/JDM concept truck, it reads as having a one piece 4" aluminum driveshaft. THat truck appeared to not be a supercab though. Maybe JIMIII can chime in. Hell, maybe we could even get a group buy on them if they are available somewhere. I am sure they are expensive though. Id even be willing to go carbon fiber...


I just called and left a message and sent an email to PST regarding a one piece driveshaft.

[Light02atl]

The engineers for PTS are out until next week. They are going to get back to me then.

[hennie]

I think a 1 pce driveshaft should work, you only need to cut away the little hump, just at the point where it is mounted to body right now.

Hennie

[hennie]

So I now measured the angle at the crankshaft pulley( or at the balancer to be specific) and at the balancer it has a 3 degrees negative angle.
does this mean I need to order 6 degree shims to get the axle lined up with the crankshaft? Or should I just get in between and order some 4 degree shims? the later to avoid too much difference in angle at the end of the transmission??

Hennie