Grinding noise

[surfindave]

Hey Guys
Just got a SWB nissan patrol for comp work me sasd runner for rocks .
The SWB had a 1" coil lift and ive gone and made it 3"
While i was at it put some 2nd hand 4.6 ratios in it.
B4 the lift i had a slight grinding noise when backing of the gas so i guess on coast or overun .
Well now im sitiing higher the grind is farkin 3 times a loud seems to come from the diff so rippd the centre out all bearings are good and backlash the pattern for mesh isnt the best .
But with the old gears it had the grind and good mesh .
Where the fark could the grind be coming from ?? 
Any ideas .
Im rebuilding the driveshaft with new unis and a ballance could the unis make a grinding noise.
The diff has been setup by my diff guy who sets up me toyota stuff and spent all day yest trying to get a better pattern but ive gota do with what it has.
Also it seems to get worse at higher speed then if i put clutch in to change up or down it grinds . .
Could it be the noise coming from the chain in the tcase??
Thanks Dave

[scheid6996]

well are u sure its commen rom the difdfd? could be t case or tranny

[Shamb]

Its your tranny, talk to toynorcal. He had a bad tranny that did the same thing.

[irishracer34]

  i bet the muffler bearings went bad!

[79coyotefrg]

dang son that input bearing in your tranny is toast,   talk to MrWillyMammoth,  he might have 4 or 5 of those trannies laying around,   

[yodersgirl]

did you have you'r dif guy check the pinon on the gears    i have that prob too i looked onto the t case and driveline it wasent the prob come to find out my 5.29 gears were cut wrong    iv'e heard it dose'nt hapen too offten so i'm looking into new gears you should check into it

[dentedfender]

Sorry to hi jack but mine makes the same type of noise, but only when I'm going about 55 then if i  let of the gas or have the gas about 1/4 throttle it makes a grinding noise. It goes away when i give it more than 1/4 throttle, it also does it in neutral at that speed, any ideas?