VLSD swapped but whines on a 240sx

[TrukillaS14]

Ok so I recently posted a vid about me about to swap my welded diff to a VLSD. SO i swapped it with Valvoline 75w-90, it works great on the turns and locks when I need it to, BUT however, I have this whining sound when I go 15mph and higher and its louder when I let go of gas and decelerate. Whining was there b4, on the welded diff but not as loud. Please help, the question that I can answer now is that no there is no leak I checked recently.

[sjbsuperman1425]

any way you can post a video of the sound? Is it a high pitched whine or a low growl? I think I have something like this going on with my open diff actually. I was coasting down and it sounded like a siren or a flat tire or something.

[the converted]

Did you just swap the carrier into your diff housing or did you do a whole housing swap? If it was the first, you probably got the backlash off a little bit, and that will cause the whine.

[TrukillaS14]

its actually a high pitched whine, no growl, but it a VLSD I had the same thing on my open diff but it was welded.

[ChristianKustomz]

Just to throw this out there but if you had this problem before the swap, are you sure your wheel bearings did not have problems prior? I am not sure of what your sound is but I know I have had many customers with weird rear end noises which has come down to over looked wheel bearings. Any time you change a rear end you should replace the seals and bearings (unless they areless then a year or two old). Usually they make a low noise and often reproduces a bass sound in the vehicle or as lopping noise. Hope this helps.

[TrukillaS14]

ok so, the housing that had the VLSD the two big holes that connect to the frame where to big for the bolts I had for the 240sx so I used the stock housing. I took out the welded diff. from housing (1), and also took out the VLSD from housing (2), the axle shaft splines where different than the ones from housing (1), so I put the axle shafts from housing (2) into ok lets just say H1. The backlash on the welded diff. was pretty bad, and the one on the VLSD seems barely used, so I kept the VLSD one on. Ok this is wat I swapped into H1, H2 axle shafts, H2 VLSD w/ ring gear, H2 bearing caps and bolts, H2 spacers and bearings. and last but not least H2 diff cover because the bolts on the H1 diff cover was basically torqued on by previous owner. So yea. I was thinking the same thing bout the backlash and ring gear. Will I have to break it in or will it cause problems later on. Help

[TrukillaS14]

yea it helps but it wasnt that bad at first and when we were swapping it out I checked the bearings they seem fine they can possibly last couple more years. I was a low whine b4 the swap. But I am considering switching the bearings now cuz of the noise, re-doing everything.

[the converted]

So you only took the carrier and the ring gear from the VLSD housing? You'll have to swap the pinion over as well to get rid of the whine. Also, you might want to actually measure the backlash of everything in the VLSD housing, so that you can try and get the same number in the other housing. If you don't get that umber right, you'll never get rid of the noise because the gears work harden themselves over time.

[sjbsuperman1425]

from my gathering of information the past week this is what you can do:

use the VLSD Carrier and output shafts with the open diff. ring gear, pinion, and case UNLESS the ring gears are the same (have same number of teeth).

[Klits562]

everyone I've talked to that have lsd's say theres whine and they just use an additive to make it stop.I thought diff whine was just a normal thing

[ChristianKustomz]

No car should ever make a noise. If it does it means something is wrong and will cause problems in the future. I agree though. You need to measure the backlash and check the tollerances. Make sure when you torque the pinion gear in with a new crush ring you get it exactly torqued to spec. If there is a noise it means that something is grinding the wrong way. I know there are some people who will use thicker fluid to hide the noise but the problem is it just maskes the real problem. Kind of like putting a bandaid over a bullet wound. Doesn't fix the problem but covers it up. Same thing. Eventually something will wear out or break. Best thing to do is measure the ring and pinion gear. Measure the backlash. Use a feeler gauge and measure the distance between the teeth. Look for any worn spots on the teeth. Look for anything that has grind marks or shiny spots. Look for anything that looks like it is bent or misaligned. Also make sure they are fitting in the housing properly too. These things will at least narrow down the possibilities of these things. If all these are ok then that rules out alot of common issues.