I might need a new rear end

[35th-ANV-SS]

so then...what should i do to get my whine to stop?

a) turn up radio
b) get louder exhaust
c) get cut-out and run cut-out
d) get louder stereo

[INMY01TA]

so then...what should i do to get my whine to stop?

Well you basically have three options.


1. Rebuild your stock rear. Cost a couple hundred bucks but I never recommend putting any money in the stock rear.

2. Buy a twelve bolt/9 inch. This will cost you several thousand dollars. Your new 12 bolt may end up whining too from whatever you did to make your stock 10 bolt whine. My 12 bolt screams.

3. Live with it. My 10 bolt howled like a scalded dog. Bought a 12 bolt and sold my 10 bolt to a guy with a cammed SS, he wanted it cause I had 4:10 gears in it and only charged him $100. He made somethin like 20 passes in it and it never broke before he bought a new 9 inch.


I got used to the gear noise, reminds me it's a muscle car. I have heard 9 inches are better at keeping quiet after track abuse.

[BashamWS6]

so. in conclusion...run it till it cant take the abuse anymore?

[INMY01TA]

so. in conclusion...run it till it cant take the abuse anymore?

Well what kind of abuse? I'm not sure what your plans are with the car. If it's gonna see track time then yes I'd just get a 9 inch. Just daily driving and playing around on the street it's not necesary.

[35th-ANV-SS]

I have a Moser 9" with 4.11 gears and I can't hear my rear end at all.

[bberretta]

I didn't see anywhere near a %17 drop in my milaege. Alot of people that I think never actually done the gear swaps are the ones that post about gears affecting their milaege.

Seriously? You really want to make a claim like that? I've done gear swaps in 5 cars- 1971 Chevelle Malibu, 1970 Nova, 1955 Chevy, 1994 Chevy Silverado, and my 2000 Firehawk (I also changed the transaxle in a 1987 Honda CRX from the HF to an Si trans which changed the final gear ratio and changed the fuel economy). I have some experience with this, so I'm not sure how much validity there is to your claim.

Notice I did not say a 17% change in mileage, it is a 17% difference in ratio between a stock 3.42 and a 4.11 (4.11 - 3.42 = .69 .69/4.11= .167 or 16.7%). The mileage is more like 5-10% and will differ depending on how it is driven. This means on a car that gets 17 mpg, you would lose between .85 and 1.7 mpg (17/.05= .85). That's it. You may not notice it too much, but there is a change whether you want to admit it or not because the motor is running at higher RPMs to do the same work that it was able to cruise along at before. It's not a huge change, but a change none-the-less. Anyway, worrying about MPG in a V8 is like worried about sand in your shorts in the middle of the desert- sure it's an issue, but not the biggest one you face!

Basham- just run it until you can afford the upgrade to a 9" or a 12 bolt. If it's not clunking and there's not any excessive play, you can live with the whine. You can try changing out the fluid for a synthetic (don't forget the posi additive!) and see if that will quiet it down, but don't count on it.

[BashamWS6]

Seriously? You really want to make a claim like that? I've done gear swaps in 5 cars- 1971 Chevelle Malibu, 1970 Nova, 1955 Chevy, 1994 Chevy Silverado, and my 2000 Firehawk (I also changed the transaxle in a 1987 Honda CRX from the HF to an Si trans which changed the final gear ratio and changed the fuel economy). I have some experience with this, so I'm not sure how much validity there is to your claim.

Notice I did not say a 17% change in mileage, it is a 17% difference in ratio between a stock 3.42 and a 4.11 (4.11 - 3.42 = .69 .69/4.11= .167 or 16.7%). The mileage is more like 5-10% and will differ depending on how it is driven. This means on a car that gets 17 mpg, you would lose between .85 and 1.7 mpg (17/.05= .85). That's it. You may not notice it too much, but there is a change whether you want to admit it or not because the motor is running at higher RPMs to do the same work that it was able to cruise along at before. It's not a huge change, but a change none-the-less. Anyway, worrying about MPG in a V8 is like worried about sand in your shorts in the middle of the desert- sure it's an issue, but not the biggest one you face!

Basham- just run it until you can afford the upgrade to a 9" or a 12 bolt. If it's not clunking and there's not any excessive play, you can live with the whine. You can try changing out the fluid for a synthetic (don't forget the posi additive!) and see if that will quiet it down, but don't count on it.

would autozone have this stuff?

[bberretta]

Yes. I've saw someone post on here recently that they used the Royal Purple stuff that says it has the additive in it but it didn't do so well and when they called Royal Purple they suggested adding the Posi additive. I'd just go with the Mobil1 Synthetic stuff and get a bottle of the GM additive. You'll also need a tube of the black silicone sealant to seal the cover and a can of brake cleaner to clean stuff up with (unless you have access to a parts washer.) All in all, probably cost about $25-30 to do it at the most.

[BashamWS6]

So get the additive from a GM dealer and the mobil1 from autozone(or whereever)?
What are we talking...30 min job or so?
And how long should i let it sit?

[INMY01TA]

Personally I prefer dino 80/90 gear oil + the limited slip additive.

[bberretta]

Dino is really good stuff. Where have you found it?

As for how long to let it sit, here's what to do:

Loosen all 10 bolts with the drain plug beneath the housing. Leave the bottom bolt in but take out the four on either side and then back the others out about half way. Pop the cover up and let it drain. Leaving the bottom bolt in allows you to control the flow of the fluid. Gear lube stinks to high Hell, so be prepared!

Once the fluid slows to a trickle, pull the cover the rest of the way off and clean it up. Scrape all the gasket and sealant off and clean the magnet in the cover. Use a scuff pad/scotch brite pad to clean up the surface where you're putting the sealant on both the cover and the rear and spray with Brake cleaner to get a good clean surface.

Lay a bead of silicone on the cover. I usually let it set up for a second to tack up. If you let it sit while you pull the fill plug out, that's usually long enough- you don't want it to dry. Put the cover on and torque all the bolt to spec. Don't over tighten- you don't want to break off bolt or warp the cover.

Squirt the additive in the fill hole and then start adding fluid. Fill until it is level with the fill hole. Put the plug back in and you're done.

I think the only tools you'll need are a 10mm socket, a 3/8" ratchet and a 6" extension for the ratchet (that way you can get to the fill plug.)

[BashamWS6]

Dino is really good stuff. Where have you found it?

As for how long to let it sit, here's what to do:

Loosen all 10 bolts with the drain plug beneath the housing. Leave the bottom bolt in but take out the four on either side and then back the others out about half way. Pop the cover up and let it drain. Leaving the bottom bolt in allows you to control the flow of the fluid. Gear lube stinks to high Hell, so be prepared!

Once the fluid slows to a trickle, pull the cover the rest of the way off and clean it up. Scrape all the gasket and sealant off and clean the magnet in the cover. Use a scuff pad/scotch brite pad to clean up the surface where you're putting the sealant on both the cover and the rear and spray with Brake cleaner to get a good clean surface.

Lay a bead of silicone on the cover. I usually let it set up for a second to tack up. If you let it sit while you pull the fill plug out, that's usually long enough- you don't want it to dry. Put the cover on and torque all the bolt to spec. Don't over tighten- you don't want to break off bolt or warp the cover.

Squirt the additive in the fill hole and then start adding fluid. Fill until it is level with the fill hole. Put the plug back in and you're done.

I think the only tools you'll need are a 10mm socket, a 3/8" ratchet and a 6" extension for the ratchet (that way you can get to the fill plug.)

so whats the posibility that this will help with the whine?

[INMY01TA]

so whats the posibility that this will help with the whine?

CHanging the fluid won't help the whine.

Dino is really good stuff. Where have you found it?

Anywhere. By dino I mean non synthetic.

[bberretta]

CHanging the fluid won't help the whine.

Anywhere. By dino I mean non synthetic.

I've heard both opinions- but I honestly think it can't hurt. If the gears are off and it's whining then the only fix is to replace. The clean fluid might help quiet it down a little but it won't silence it. Best thing you could do is take it easier on the rear until you get up the money to replace it. Like I said, I drove mine for months with it whining and roaring.

[BashamWS6]

I've heard both opinions- but I honestly think it can't hurt. If the gears are off and it's whining then the only fix is to replace. The clean fluid might help quiet it down a little but it won't silence it. Best thing you could do is take it easier on the rear until you get up the money to replace it. Like I said, I drove mine for months with it whining and roaring.

so its basically your saying its hard to say when/if it will go out...???
but i really dont abuse it too much...i may all out gun it maybe twice a month in a street race or showing off...but as for that...i dont abuse it at all...hasnt seen any track time...and probably wont...

[bberretta]

Let me put it this way: my 10-bolt was in great shape. Just had it built, all new bearings, new 3.73 gear, Moser almuminum cover with bearing cap hold downs, Moser bearing cap studs, etc. Here's where things went sour: in December I put in a LS7 clutch and then in July I put 315's on the rear. The combo of a better clutch and tires that didn't give much led to my posi splitting when I downshifted hard- less than two weeks after I had the tires mounted.

Truth be said- you'll never know when the rear will go. If you drive it ideally and don't dog it much then sure, it'll last for a while. The stock rear is weak- real weak. Everytime you give it hell, you're taking a chance. There's a great sticky that goes into really good detail on this topic.

[35th-ANV-SS]

so its basically your saying its hard to say when/if it will go out...???
but i really dont abuse it too much...i may all out gun it maybe twice a month in a street race or showing off...but as for that...i dont abuse it at all...hasnt seen any track time...and probably wont...

If you don't run wide tires that are grippy or drag radials and you have relatively stock power, you more than likely will be fine. Every one is different though and some people have better luck than others.

[BashamWS6]

If you don't run wide tires that are grippy or drag radials and you have relatively stock power, you more than likely will be fine. Every one is different though and some people have better luck than others.

well i will be running street tires for a long while...
if i do infact get a procharger...my next 2 steps would be a rearend and clutch

[35th-ANV-SS]

well i will be running street tires for a long while...
if i do infact get a procharger...my next 2 steps would be a rearend and clutch

better get SFC, LCAs also...and better tires.

[BashamWS6]

see thats the thing...if i get a Procharger...then i am bustass broke...
thats why i dont know if getting the procharger would be a good idea right now...
should i focus on my suspension right now?
here what im highly considering...
Moser 12 (4.11 gears|33-spline|1350 Yoke|Factory studs and rear brakes|stock width|chrome cover|no sway bar mount kit|4-channel ABS exciter rings|3Hole LCA brackets)
UMI SFC 2pt weld in
ARH 1 7/8 with ORY
SLP LMII
O2s and MSD Plug Wires
SLP Lid
......
OR
......
get the procharger
and cross my fingers