S15 helical diff grinding - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

gpeele · 12-07-2005, 04:45 PM

this is a s15 helical diff installed in a spare s13 non abs pumpkin with the correct output shafts and brand new shims, bearings and seals. all installation was done by a shop sometime ago but the shop has since closed.

just today i had the pumpkin swaped out with my stock one and it was making a loud grinding noise, like loud enough to be heard when the rear is jacked up and the wheels spin freely when the accelerator is pressed. when on the road the noise is much louder and reverbs through the car. i cant take it back to the original shop for obvious reasons, so what could be the problem, bad shims, crappy fluid (75w90 gear oil is in there now). are helical lsds themselves known to go bad? any help will be appreciated.

thanks.

Al_S14 · 12-07-2005, 04:52 PM

I have yet to hear S15 lsd go bad... they are durable and dont wear out like clutch type. My best guess they screwed up one of the bearigns ... hard to tell without looking at it.
Where in Chesapeake are you? I may be interested in getting that from you if you dont feel like messing with it. Give me a call 6153421

wootwoot · 12-07-2005, 08:25 PM

Bearings or shimmed improperly; both are easy to fuck up.

gpeele · 12-07-2005, 10:17 PM

sorry man, not really interested in selling the diff i just want it to work. i guess ill have to take it by a transmission shop and see if they can tell me whether its the shims or bearings, im just glad to hear that the lsd itself shouldnt be the problem.

thanks for the replies.

wootwoot · 12-08-2005, 02:26 PM

No but the lsd could be ruined if shimmed improperly...

96240sxSE · 12-08-2005, 06:40 PM

Have a shop(a good one) take a look at the wear patterns on the teeth of the r&p. The wear pattern will tell a good tech if the diff was shimmed improperly. If you are lucky, you may just have to buy a new r&p, not the entire assembly.

nlzmo400r · 12-08-2005, 06:46 PM

take it out, and reinstall it with new shims and bearings

kandyflip445 · 12-08-2005, 08:40 PM

^^^What he said. Inspect for damage. When you drain out the fluid into a pan run a magnet through it and see just how much metal there is. If there is a shitload then you need to inspect everything. If there is minimal metal then you should still check but it's more likely to be ok.

12-07-2005, 04:45 PM	#1
gpeele Join Date: Jul 2005 Location: Virginia Posts: 31 Trader Rating: (0) Feedback Score: 0 reviews	S15 helical diff grinding this is a s15 helical diff installed in a spare s13 non abs pumpkin with the correct output shafts and brand new shims, bearings and seals. all installation was done by a shop sometime ago but the shop has since closed. just today i had the pumpkin swaped out with my stock one and it was making a loud grinding noise, like loud enough to be heard when the rear is jacked up and the wheels spin freely when the accelerator is pressed. when on the road the noise is much louder and reverbs through the car. i cant take it back to the original shop for obvious reasons, so what could be the problem, bad shims, crappy fluid (75w90 gear oil is in there now). are helical lsds themselves known to go bad? any help will be appreciated. thanks.

12-07-2005, 08:25 PM	#3
wootwoot Post Whore! Join Date: Jan 2004 Location: sarasota florida biatch Age: 39 Posts: 3,850 Trader Rating: (0) Feedback Score: 0 reviews	Bearings or shimmed improperly; both are easy to fuck up. __________________ I'm from Florida so I'm probably a bit more strange than you

12-08-2005, 02:26 PM	#5
wootwoot Post Whore! Join Date: Jan 2004 Location: sarasota florida biatch Age: 39 Posts: 3,850 Trader Rating: (0) Feedback Score: 0 reviews	No but the lsd could be ruined if shimmed improperly... __________________ I'm from Florida so I'm probably a bit more strange than you

12-08-2005, 06:46 PM	#7
nlzmo400r Zilvia FREAK! Join Date: Oct 2003 Location: louisiana Posts: 1,248 Trader Rating: (0) Feedback Score: 0 reviews	take it out, and reinstall it with new shims and bearings __________________ 'my drinking team has a racing problem' [email protected] - gt32 .6bar

12-08-2005, 08:40 PM	#8
kandyflip445 Post Whore! Join Date: Sep 2002 Location: Arden, NC Age: 40 Posts: 4,460 Trader Rating: (1) Rides Gallery: kandyflip445 Feedback Score: 1 reviews	^^^What he said. Inspect for damage. When you drain out the fluid into a pan run a magnet through it and see just how much metal there is. If there is a shitload then you need to inspect everything. If there is minimal metal then you should still check but it's more likely to be ok. __________________ My 240 vBgarage

12-07-2005, 04:52 PM	#2
Al_S14 BANNED Join Date: Jan 2005 Location: Chesapeake VA Age: 40 Posts: 405 Trader Rating: (0) Feedback Score: 0 reviews	I have yet to hear S15 lsd go bad... they are durable and dont wear out like clutch type. My best guess they screwed up one of the bearigns ... hard to tell without looking at it. Where in Chesapeake are you? I may be interested in getting that from you if you dont feel like messing with it. Give me a call 6153421

12-07-2005, 10:17 PM	#4
gpeele Join Date: Jul 2005 Location: Virginia Posts: 31 Trader Rating: (0) Feedback Score: 0 reviews	sorry man, not really interested in selling the diff i just want it to work. i guess ill have to take it by a transmission shop and see if they can tell me whether its the shims or bearings, im just glad to hear that the lsd itself shouldnt be the problem. thanks for the replies.

12-08-2005, 06:40 PM	#6
96240sxSE Join Date: May 2003 Location: Oregon Posts: 15 Trader Rating: (0) Feedback Score: 0 reviews	Have a shop(a good one) take a look at the wear patterns on the teeth of the r&p. The wear pattern will tell a good tech if the diff was shimmed improperly. If you are lucky, you may just have to buy a new r&p, not the entire assembly.