Diff angles

[Malcolm]

Hi all, just trying to fix a vibration from the drive train. Had the tailshaft balanced, thats all good.
Now I just have to correct the tailshaft angle, does anyone know where you can get diff wedges from as I need a couple of degrees uplift on the front of the diff to stop vibration.

[Craig]

Mate you used to be able to git them from 4x4 accessory outlets or spring makers try carrols http://www.carrolls.com.au/

[Thommo]

I remember 'Lakewood' used to make wedges to fine tune their tramprods

[karsten]

my commadore suffers real bad mal ,,if it is not had all the wheels balanced perfect ,,10 grams out on even a back wheel and it shakes ,,,just a thought

[oldnek]

Now I just have to correct the tailshaft angle, does anyone know where you can get diff wedges from

Mal, Why don't you try wheel alignment shims first off, then you will know if your going in the right direction, before outlaying dollars on wedges that maybe wrong. Just a thought.

John

[Sammy]

i had the same problem in the Torana after putting the T700 in it, when i did the borg warner diff in it i decided to adjust the angle, got a few measuring tools and eventually ended up changing the angle 4 degrees .... it works a treat, used to get vibration over 110kms but now its heaps better!!

[Malcolm]

Thanks for the input guys,

I ended up getting a angle guage and doing a bit of stuffing around with lifting the back of the box a bit and the front of the diff a fair bit.

I ended up cutting down a pair of lowering blocks to the measurement I set the diff on so we'll see how that goes. It certainly looks a lot better anyway.

Cheers

[Harko]

cut n weld it right , 2.5-3 degrees

[Sammy]

harko, are you say diff nose pointing up at 2.5-3 degrees ?

i don't really know that it came be the one measurment for all cars, especially if they have aftermarket crossmembers ....

i know in my case (Torana) the gearbox was as far up the tunnel as i could get it and it was still pointing down at 5 degrees different to the diff .... i ended up changing my diff to 4 degrees up and this has fixed alot of my vibrations!

[Harko]

I see your point Sammy , from my knowledge every diff I have measured is 2.75 - 3.0 degrees .
Id say an aftermarket crossmember "should" and I say that loosely -should be set as per the factory part it is replacing or it may be possible that this may cause injury , Or it should be stated in the sale that the part is not a replacement .

Be aware also that you shouldnt set the diff angle exactly the same as the gearbox malcom ,that can cause vibration also - no preload

[Malcolm]

Thanks,

Prior to my changing anything I picked the brains of the guys that balanced the tailshaft. They gave me a good run down of what the angles should be.
Will be trying it out tomorrow as I have to take it for a 2 hour drive to get the gearbox sorted

Cheers

[thropzed]

Hey Malcom, Have you got any driving pics yet? Where in brisvegas are you getting your gearbox sorted? would love to come out to see you and the Yellow Beast!!!
Cheers Theo Z.................

[Sammy]

i'd be interested to hear your tailshaft guys theories mal cause i went through a similar thing and i was having lots of trouble getting a definative answer as to the best way to do it....

first off i had people telling me i needed to get the tailshaft and unis as straight as possible, eg. minimal bend from the unis but then i read alot of stuff on the internet saying if there is a line drawn through the crank and gearbox shafts from front to back then this is measured and the angle says that its pointing down on a 2 degree angle, then you want to make sure the line through the pinion shaft in the diff is nose up about the same

bearing in mind things like point it down more for drag racing but not as much for street etc so with all that in my head i spoke to the bloke that shortened my tailshaft and from his limit knowledge he reckoned that what i said above was the better way to go than just lining them up by eye.

i know a bit about harmonics etc and i understand why you'd want to have the pinion shaft and gearbox/crank all in a similar axis.

[Malcolm]

Hey guys, the gearbox is still shit. After a 2 hour drive to the diff guys it came home still stuffed.
Now it only brining up the 1 code (85 Transmission slipping) and there saying its the converter causing the problem as when its slipping when locked it goes into safe mode stopping it from changing into top and recording the 85 code.

And the tail shaft is still not right. My measureing was a bit on the quick side so it was hit and miss as to weather it was going to be correct.

Sammy how the angles were explained to me is the gearbox output shaft and the pinion should run on a paralell plane and when the tailshaft is in it should have a 3 degree max. angle on each end. The tail shaft, pinion and output shaft should not be in a straight line or it won't work.

The problem I'm still having is the pinion is still on a different angle to the output shaft.

Hey Theo no driving pickies yet. Will be taking the car down to Caboolture early saturday to meet the engineer and get all that side of it done.

[karsten]

hey mal i dont know if this will help but anderson gearbox and diff at acacia ridge deal with truck stuff but i guess the principle is the same just bigger,,but the boss man there knows alot obout this stuff ,,as ive had to ajust angles on trucks over the years to stop vibes they cant run straight cause they shake themselves to bits but it may be worth a call they would know other repairers that would have charts that tell you sharft length verses angles and requirements ,,,but they mite know ,,