Diff backlash problem?

[Anthraxnz]

Hi

the Diff in my VN exec has excessive play, by that i mean if i accelerate then decelerate then accelerate i hear a "bonk" kind of noise coming from the rear.

will replacing the diff center fix this or will i have to get the entire diff reset?

also will my diff blow if i keep driving it like this? i only drive on the motorway really and dont do much start stop stuff.


Thanks

[Emackulation]

Sure its not the tailshaft joints? Can they make this noise?

[VN_Luke]

as mack said, it could be uni joints

could also be caused by center bearing on the tail shaft.

apparently small noises from those parts can be significantly amplified and make it sound like a much bigger movement.

however if you chuck your car in neutral, get under there and move the tailshaft with your hands, and it's CLEARLY got lots of play in it (i.e. the diff yoke/flange turns/wiggles as well) then you have excessive backlash (possibly amongst the other problems too).

It won't "blow up" as such, but you will be wearing your gears excessively and making them significantly more prone to failure. The issue could be that the gears just need to be re-aligned - a diff guy should do it for about 100 bux. Failing that, you might have excessively worn gears that don't mesh nicely, in which case you could buy new gears and get them fitted up, or just buy a whole new diff for 50 bux and fit it up in a few hours

let us know how you go!

[Anthraxnz]

cheers for the help, i had it on a hoist a while ago but i think it was in park. there was some play, ill have a look this weekend.

by gears do you mean gearbox or diff gears?

[Emackulation]

cheers for the help, i had it on a hoist a while ago but i think it was in park. there was some play, ill have a look this weekend.

by gears do you mean gearbox or diff gears?

He means Diff.

[VN_Luke]

there'll be a little bit of play, but shouldn't be 'heaps'

[VNexecutive]

yeah if theres nearly half a turn of play like mine you know its sharted ahahaha

[Anthraxnz]

checked it this morning and took a video of it.

[vnv8driver]

perfectly normal mate, by the sounds of the video you need uni joints.. also have a bash on the centre bearing, if theres play it will need replacing also.

when you drop it into gear from neutral/oark do you hear a clunk? also is there any vibration?

[Anthraxnz]

yeah i do hear a clunk every time. sometimes its loud sometimes its not so loud, depends on what the revs are doing.

[Pub247]

uni joints imo, replace them first its pretty compared to what a diff costs

[Turtle57]

I've got the same sound from my diff. However my box is manual. Been like this for a few months now. In a few weeks we are chucking a LSD in it

Also, cause my box is manual and the diff came from an auto, what will need to be changed?

[-vkhg]

ey fellas,

ive got a VN Calais 5.0L auto.

i have kinda the same problem. the only thing different i have is that when im driving along at a constant speed sometimes i hear fast knocking coming from the rear. when its under load (going up a hill or accelerating) its fine. when i put it in any gear apart from neutral, it clunks something cronic. also backing off the accelerator it clunks and when reapplied it clunks. i havent got a hoist so i cant really check it out myself. im close to buying a new diff centre and paying someone to chuck it in. should i do this or look into it further first ?

[calais_cruzin]

Also, cause my box is manual and the diff came from an auto, what will need to be changed?

Its the same eh man nothing will need to be changed over, the only diffferece between auto n manuals was the front half of the tailshaft.

vkhg, do what the OP did n move ur tailshaft see if that has the excess play in the uni's or center bearing, b4 lashing out on a diff

[-vkhg]

fixed my problem.

i was told that if my uni joints were shagged that it would vibrate the whole car and i wasnt experiencing anything like that. so i went out on a limb and bought an lsd diff from ebay for $300 (immaculate condition) and put it in the car. when i took the old one out i found that one of teeth on one of the spider gears was broken so that explains the slop. so with the new lsd in the car problem fixed. twin peggin now too