Extremely pissed off Can you help?

**illcul8troffcr** · 10-26-2008, 03:41 PM

So I decide to do some preventive maintenance. A little manual overhaul.
Now first off I had no problems or sounds in my rear end or transmission and everything shifted fine. That being said..

I took my car in to get the spark plugs and wires changed. Decided to do the transmission fluid and filter as well. And decided to do the rear end fluid too.
My car has 80,000 on the odometer.

I get the car back a week ago and it is literally banging into first gear, shifting very hard. The guy said he "bumped up the pressure in the transmission" So I drove it for a few days and then it started making some noise in the rear end to. So I'm like theres no way this shit is right so I was going to take it back to him to fix it Friday.. Had a docs appt Thursday.. Driving to it and it sounded like a constant clunking sound as it rolled slow. I take it to the dealership that was close by .. they check the rear end and tell me ..

They removed the rear cover and saw no visual problems.. removed both axels & carrier assembly..found sider gears are shot and pinion was too tight and center pin loose.. needs all bearings and carrier assembly ..Also wanted to charge me .. lol $2,300 dollars to fix it

So in my opinion the guy who did the initial work fucked something up. I'm going back over there tomorrow to handle it.

A few questions I need answered..

I know the rears in our cars (SS) have to have a certain additive.. what is it called and what amount.. as well as what fluid goes in them?

Any expert info on this would help.. thanks!

**Too Fast** · 10-26-2008, 04:04 PM

A simple fluid change in the differential won't cause a problem like you describe, sounds like bad timing on that fluid change. And no, if they forgot to put the limited slip additive in, it won't cause massive destruction like you report, that additive is to quiet the clutch packs. Our cars use synthetic 75w90 gear oil, even non-syn fluid won't cause an immediate failure like you describe.

Now for the trans issues, upping the line pressure should not have caused a problem unless you already had imminent failure. It could be the hard 1st gear engagement caused the (almost ready to fail anyway) diff to fail. Probably your next hard launch at the track or street would've caused this anyway.

I am an ASE Master Certified auto tech for the last 20 years, I hope this info helps you.

**illcul8troffcr** · 10-26-2008, 04:09 PM

Originally Posted by Too Fast

A simple fluid change in the differential won't cause a problem like you describe, sounds like bad timing on that fluid change. And no, if they forgot to put the limited slip additive in, it won't cause massive destruction like you report, that additive is to quiet the clutch packs. Our cars use synthetic 75w90 gear oil, even non-syn fluid won't cause an immediate failure like you describe.

Now for the trans issues, upping the line pressure should not have caused a problem unless you already had imminent failure. It could be the hard 1st gear engagement caused the (almost ready to fail anyway) diff to fail. Probably your next hard launch at the track or street would've caused this anyway.

I am an ASE Master Certified auto tech for the last 20 years, I hope this info helps you.

It's literally snatching into first gear now or reverse.. he said he changed a shifting spring? in the transmission. I have only went down the track with this 3 times. The car is babied man haha

**2001NBMZ28** · 10-26-2008, 04:10 PM

Well the owners manual calls for 4oz of GM limited slip axle lubricant additive for G80 RPO axles, but most aftermarket brands say it's included or not needed for their products - ask what they put in there.

Why mess with or "bump" the line pressure for just a fluid/filter change? If the fluid level is correct I'd check for any trans codes, some command 100% line pressure when set - ask what/how they "bumped" it.

Not an expert by any means, just my thoughts.

**0rion** · 10-26-2008, 04:11 PM

it's called limited slip additive (part number 1052358) and comes from the dealership in 4oz bottles. I've bought it at a parts store too but it's a little bigger bottle from the parts store. Just takes a few ounces. It also depends on if you have an auburn or torsen rear. The auburn's require the additive and the torsens don't. Maybe someone will correct me if I'm wrong but I think 00+ all had torsens and don't require the additive. I'm not positive on that so maybe someone that knows for sure will chime in.

**Sarge** · 10-26-2008, 04:11 PM

Me thinks he forgot to put the limited slip additive in it leaving the LSD engaged and blew up the gears/pinion as you merrily rounded corners etc. Seen it before and what you described tells me he did not put anything but the oil in your pumpkin.

**Too Fast** · 10-26-2008, 04:16 PM

Originally Posted by Sarge

Me thinks he forgot to put the limited slip additive in it leaving the LSD engaged and blew up the gears/pinion as you merrily rounded corners etc. Seen it before and what you described tells me he did not put anything but the oil in your pumpkin.

I've always read/heard the reason for the additive is only to quiet the clutch packs around corners? I don't work in a differential shop, so I am not massively experienced with that.

**Too Fast** · 10-26-2008, 04:20 PM

Originally Posted by illcul8troffcr

So I decide to do some preventive maintenance. A little manual overhaul.
Now first off I had no problems or sounds in my rear end or transmission and everything shifted fine. That being said..

I took my car in to get the spark plugs and wires changed. Decided to do the transmission fluid and filter as well. And decided to do the rear end fluid too.
My car has 80,000 on the odometer.

I get the car back a week ago and it is literally banging into first gear, shifting very hard. The guy said he "bumped up the pressure in the transmission" So I drove it for a few days and then it started making some noise in the rear end to. So I'm like theres no way this shit is right so I was going to take it back to him to fix it Friday.. Had a docs appt Thursday.. Driving to it and it sounded like a constant clunking sound as it rolled slow. I take it to the dealership that was close by .. they check the rear end and tell me ..

They removed the rear cover and saw no visual problems.. removed both axels & carrier assembly..found sider gears are shot and pinion was too tight and center pin loose.. needs all bearings and carrier assembly ..Also wanted to charge me .. lol $2,300 dollars to fix it

So in my opinion the guy who did the initial work fucked something up. I'm going back over there tomorrow to handle it.

A few questions I need answered..

I know the rears in our cars (SS) have to have a certain additive.. what is it called and what amount.. as well as what fluid goes in them?

Any expert info on this would help.. thanks!

Originally Posted by illcul8troffcr

It's literally snatching into first gear now or reverse.. he said he changed a shifting spring? in the transmission. I have only went down the track with this 3 times. The car is babied man haha

So what is the full story, only a simple trans fluid and filter, or did you ask the shop to do more? If he changed other things without your approval, you do have some issues with the shop...tell the truth now, don't label us mechanics as imbecils. Did you ask him to firm up the shifts as well??

**Sarge** · 10-26-2008, 04:23 PM

Well the short and sweet on the LSD additive is this.....well let me start at the start

Our LSD have clutches that catch and engage the axles....now going around a corner under power you do not want both axles turning the same RPM.....so the clutches dis- engage and allow one wheel to spin freely....then as you straighten out the clutches re-engage putting power to both wheels. The chatter you refer to is the clutches chattering dis-engaging and re-engaging......
The additive is slippery as snail spit and allows the clutches to slip when only under minimum power thus killing the chatter....and fully engage under power.
What happens when you do not use any additive is the clutches stay engaged and you got massive torque trying to tear your pinion/gears apart as the clutches stay engaged all the time.
What this guy is describing is clearly the results of those clutches being engaged all the time and the stress onthe gears/pinion is too great.

**Goldcuffs** · 10-26-2008, 04:24 PM

Did you ask for the line pressure to be changed or did he take that upon himself? If he did I would pissed, If you asked you might be stuck with a bill.

**Too Fast** · 10-26-2008, 04:25 PM

Originally Posted by Sarge

Well the short and sweet on the LSD additive is this.....well let me start at the start

Our LSD have clutches that catch and engage the axles....now going around a corner under power you do not want both axles turning the same RPM.....so the clutches dis- engage and allow one wheel to spin freely....then as you straighten out the clutches re-engage putting power to both wheels. The chatter you refer to is the clutches chattering dis-engaging and re-engaging......
The additive is slippery as snail spit and allows the clutches to slip when only under minimum power thus killing the chatter....and fully engage under power.
What happens when you do not use any additive is the clutches stay engaged and you got massive torque trying to tear your pinion/gears apart as the clutches stay engaged all the time.
What this guy is describing is clearly the results of those clutches being engaged all the time and the stress onthe gears/pinion is too great.

Hmmmmmmmmmmmm........................I guess from that perspective it could possibly be the problem, but I still would think the OP already had a problem that was almost ready to reveal itself.

**Sarge** · 10-26-2008, 04:29 PM

Well sure.......but he would have heard it starting to whine/clunk I would think before this. As for the bumping of the shift pressure.....he probably told the mechanic "something" and the guy just adjusted his shift pressure....I doubt that has anything to do with his rear end though...

**illcul8troffcr** · 10-26-2008, 04:33 PM

Originally Posted by Too Fast

So what is the full story, only a simple trans fluid and filter, or did you ask the shop to do more? If he changed other things without your approval, you do have some issues with the shop...tell the truth now, don't label us mechanics as imbecils. Did you ask him to firm up the shifts as well??

no I did not ask him to change anything .. just simply replace the fluid and filters on everything

**illcul8troffcr** · 10-26-2008, 04:34 PM

Originally Posted by Goldcuffs

Did you ask for the line pressure to be changed or did he take that upon himself? If he did I would pissed, If you asked you might be stuck with a bill.

no I didn't ask for him to change anything like that

**Sarge** · 10-26-2008, 04:35 PM

Well he should have left it be then.

**Too Fast** · 10-26-2008, 04:36 PM

That's another reason I am asking the OP to be fully truthful. No noises at all previously and now suddenly a trans issue as well as differential issues?

Not saying some dimwits didn't add the additive, as I have seen many 18-20 year old "wet behind the ears" here where I work. Hell, a lot don't even know how to raise a car on a lift, I learned that way back when I was 15 in high school.

**Too Fast** · 10-26-2008, 04:39 PM

Originally Posted by illcul8troffcr

no I did not ask him to change anything .. just simply replace the fluid and filters on everything

If so, you may have a good case here. Can you get it in writing or have a copy of the invoice stating he changed some kind of spring in the trans without your persmission/asking him to? Or will the shop admit to doing it and not telling you about the possible consequencies? Then they could be SOL. Up the stream without a paddle. Massively on the hook for a trans repair or diff rebuild.

Good luck.

**illcul8troffcr** · 10-26-2008, 04:41 PM

Originally Posted by Too Fast

That's another reason I am asking the OP to be fully truthful. No noises at all previously and now suddenly a trans issue as well as differential issues?

Not saying some dimwits didn't add the additive, as I have seen many 18-20 year old "wet behind the ears" here where I work. Hell, a lot don't even know how to raise a car on a lift, I learned that way back when I was 15 in high school.

No like I said when I got it back it was shifting really hard.. literally if I was on the gas a little bit going around a curve it would break traction going from first to second.. I didn't like it at all. I told him I'd be bringing it back to get whatever he did removed. I was just waiting a few days until I had a free day. It just so happened that it royally fucked up before that day came.

**illcul8troffcr** · 10-26-2008, 04:42 PM

Originally Posted by Too Fast

If so, you may have a good case here. Can you get it in writing or have a copy of the invoice stating he changed some kind of spring in the trans without your persmission/asking him to? Or will the shop admit to doing it and not telling you about the possible consequencies? Then they could be SOL. Up the stream without a paddle. Massively on the hook for a trans repair or diff rebuild.

Good luck.

yea he I asked him on the phone directly what the hell did he do to "bump up the pressure" and that's when he told me he changed the shifting spring. So we plan on going over there tomorrow to "talk" about it haha

**Sarge** · 10-26-2008, 04:44 PM

Originally Posted by Too Fast

That's another reason I am asking the OP to be fully truthful. No noises at all previously and now suddenly a trans issue as well as differential issues?

Not saying some dimwits didn't add the additive, as I have seen many 18-20 year old "wet behind the ears" here where I work. Hell, a lot don't even know how to raise a car on a lift, I learned that way back when I was 15 in high school.

I have a great deal of respect for the training a Master Mechanic has to go through...I know quite a few personally and they are top notch.....very attentive to detail....but as you accurately state....some dipshit probably was involved and screwed this thing up....
Unfortunetly I bet our young member ( The OP) will be shelling out the bucks as there is noway in hell I know of to prove anything other than shear coincidence. It is probably better to negotiate a free labor and parts at cost deal with the mechanic.....I doubt the mechanic who did the fluid change would argue to hard on that...