Why is my rebuilt diff whining?

[TurboTapin]

I installed my rebuilt diff earlier today. Nismo GT 1.5 LSD and Speedtek Billet 3.3 Ring & Pinion. It whines rather bad on acceleration and is much worst above 60kmh. No noise when my foot is off the pedal. 

So far, I've driven it 30 minutes with a few hours cooldown in between. Will it get better as it breaks in? or are we looking at pulling the diff and bringing it back to the assembler for verification? I waited over 3 months to get my diff back, I'm not too thrilled about having to bring it back. 

[GTSBoy]

Was the gear contact pattern properly set up using engineer's blue?

If the assembler cannot categorically state that they did, and perhaps, these days, even show you the evidentiary photos....then diff out, apart, new crush washer, etc etc.

[Duncan]

Yes unfortunately I think it needs to go back. Diffs apparently need to wear in a little but they should not whine

[White GTS-T]

This might sound like a silly question, but did you put oil in it prior to fitting/driving it?

Most places that build gearboxes/diff's/transfer cases etc that I have seen, all come dry, and are not filled with any oil.

[TurboTapin]

Gear pattern, pinion depth, etc. was set. Gear had the usual yellow gear marking compound. Everything is new in the diff. I put oil in it prior to reinstall. 

I'm just wondering as you break in a new ring and pinion set, if the whining is normal. I've had new LSD's before but never an aftermarket ring and pinion and I don't know what to expect. I'm waiting on a response from speedtek as well. 

Edited September 17, 2023 by TurboTapin

[GTSBoy]

  On 17/09/2023 at 10:00 AM, TurboTapin said:

if the whining is normal

Expand  

No. Whining is either a gear mesh problem or a bearing problem (depending on the the nature of the whine. One man's whine is another man's some-other-noise).

[TurboTapin]

  On 17/09/2023 at 10:20 AM, GTSBoy said:

No. Whining is either a gear mesh problem or a bearing problem (depending on the the nature of the whine. One man's whine is another man's some-other-noise).

Expand  

I figured it would have to come off again but I was trying to lie to myself about it. I'll contact the shop and drop it off before the weekend. Possibly through their front window. 

Fun fun...

[Murray_Calavera]

  On 17/09/2023 at 10:00 AM, TurboTapin said:

I'm just wondering as you break in a new ring and pinion set, if the whining is normal. 

Expand  

I've got the same diff, mine never made any noise remotely close to what your describing. It's been perfect for the 8 or so years its been in the car now. 

[Dose Pipe Sutututu]

Offer is still there, buy my KAAZ 2 way and it comes with a full working R33 attached to it.

$40k USD and call it a deal 😎

[TurboTapin]

  On 17/09/2023 at 11:13 AM, Dose Pipe Sutututu said:

Offer is still there, buy my KAAZ 2 way and it comes with a full working R33 attached to it.

$40k USD and call it a deal 😎

Expand  

Lol inching closer and closer to taking you up on that offer. Speedtek got back to me and has been a great help. I showed them the gear marking compound and they said it's close but not perfect and to stop driving it. I'm going to pull it out this morning. 

Thanks everyone for the input. The diff saga continues ...

Edited September 17, 2023 by TurboTapin

[Duncan]

Good on them for the response

[TurboTapin]

  On 17/09/2023 at 8:45 PM, Duncan said:

Good on them for the response

Expand  

Speedtek's after sales support started very strong, but fizzled out in the end. They were originally quick to answer and stated they would assist me with correcting the issue they saw in my gear tooth pattern after I sent pictures. They even mentioned sending documentation. Then it was radio silence. I was in somewhat of a hurry as my diff place stated they wouldn't work on it again without some info from Speedtek. After a few emails and attempted calls, I did manage to speak to someone on their Facebook page; 4 days later. He seemed annoyed with the questions and answered the minimum amount and then stated "It's basic diff building, anyone can do it". 

I figured at this point, I'll call it quits with the technical support and send the info I do have and the R32 diff assembly manual to my assembler. I'm all for giving people a chance, but I'm annoyed they didn't assemble it properly the first time and I want to spoon feed them everything they could possibly need so it's not repeated. 

Edited September 25, 2023 by TurboTapin

[Dose Pipe Sutututu]

Sigh, what a head fk.

Anyhow, if you're ever coming to Australia, come take my car for a spin.

If you like the KAAZ diff enough, $40k USD and I'll throw in a free 437kW working R33 as well 😂

[TurboTapin]

My assembler finally figured out why it was making noise as he was adamant it was assembled properly. The pinion has 3 thou of runout... said he's never seen that before and wasn't impressed. He actually fell on it by accident. At this point I'm not even mad anymore... it's actually starting to get funny. 

Now I have to wait for Speedtek to send out a replacement and get it assembled once again. This diff sure is costing me a lot of time and money. @Dose Pipe Sutututu 40$K you wanted for that diff? That's a steal!

Edited October 1, 2023 by TurboTapin

[Dose Pipe Sutututu]

At least there's light at the end of the tunnel now!

I hope you get it sorted soon, and post up 3rd gear skids 😎

If not, my 2 way KAAZ with free R33 shit box is still on offer lol.

[GTSBoy]

Yes.... I guess this is one of the possible QA/QC issues that we will bump into using 3rd party gearsets.

[TurboTapin]

  On 01/10/2023 at 12:56 AM, GTSBoy said:

Yes.... I guess this is one of the possible QA/QC issues that we will bump into using 3rd party gearsets.

Expand  

Unfortunately, that it is. I'm not happy about it nor should it happen but hopefully they quickly ship out a replacement without a hassle.