Why 300 miles?
Thread Starter
Race Director
Joined: Jan 2005
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From: Bay Shore, NY 11706 MILD2WILD (M2W)
St. Jude Donor '06-'07
Why 300 miles?
Can anyone make sense of the shop manual. I just changed my diif to royal purple and did the 8 - 10 slow figures 8's as indicted (makes sense to work the fluid into the clutch packs) But it also says to "not to drive the car at wide open throttle for at least 300 miles" after a drain and refill or "scoring of the ring and pinion gears may result" This makes no sense, I could see if you rebuilt or changed the gears but on a drain and refill
Any clue?
Also the manual shows a diff cooler? What cars came with that?
Any clue?Also the manual shows a diff cooler? What cars came with that?
Last edited by Pipedreams; Apr 17, 2006 at 08:24 PM.
Team Owner
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From: God Bless America
Diff oil change
Pipedreams,
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
Thread Starter
Race Director
Joined: Jan 2005
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From: Bay Shore, NY 11706 MILD2WILD (M2W)
St. Jude Donor '06-'07
Originally Posted by 30YR W8T
Pipedreams,
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
Le Mans Master
Joined: Nov 2004
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From: Goleta CA
Cruise-In VIII Veteran
I don't remember who posted it, but he said it had to do with getting some heat into the oil for the first time, which allowed it to reach it's full protection potential. 
I'm not an expert, but that was the only logical explaination I've seen, and it came from someone who is always a good source of info.
And I wondered about the diff cooler too.
I'm not an expert, but that was the only logical explaination I've seen, and it came from someone who is always a good source of info.And I wondered about the diff cooler too.
Team Owner
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From: Far NW 'burbs of Chicago
St. Jude Donor '13
The C5 Shop Manual has the same warning, we kicked that around for a long time and never came up with a positive answer. But I still follow the 300 mile rule if i change diff fluid.
Drifting
Joined: Jul 2005
Posts: 1,343
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From: CA
Originally Posted by 30YR W8T
Pipedreams,
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
Could you notice any difference in the feel of the car after you changed the fluid? Is this stuff suppose to provide more protection than the stock fluid? What weight did you use? BTW, I wish I could answer your question, but I have no idea why you would have to do that. I wonder if this is to allow for some soak and saturate time.
As for why you've got to wait 300 miles before you use full throttle, that's a mystery to me too.
Drifting
Joined: Jul 2005
Posts: 1,343
Likes: 1
From: CA
Originally Posted by Pipedreams
Also the manual shows a diff cooler? What cars came with that?
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Team Owner
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From: God Bless America
Originally Posted by Pipedreams
I just changed it last night so not sure. I changed it because of the problem many reported that the posi clutch chaters in the cold on sharp turns. I used the 75-90 max gear.
Le Mans Master
Joined: Nov 2004
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From: Goleta CA
Cruise-In VIII Veteran
Originally Posted by Gearhead Jim
Well, it's not his car...
Besides, what's 300 miles anyway? I'll cover that this weekend when I go to the SoCal get-together and spend the day in orange county.
Le Mans Master
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From: Thousand Oaks California
Originally Posted by Pipedreams
Can anyone make sense of the shop manual. I just changed my diif to royal purple and did the 8 - 10 slow figures 8's as indicted (makes sense to work the fluid into the clutch packs) But it also says to "not to drive the car at wide open throttle for at least 300 miles" after a drain and refill or "scoring of the ring and pinion gears may result" This makes no sense, I could see if you rebuilt or changed the gears but on a drain and refill Any clue?
Also the manual shows a diff cooler? What cars came with that?
Any clue?Also the manual shows a diff cooler? What cars came with that?
As for the 300 mile rule, when the differential lub is changed, the service manual recomments the GM 75w-90 synthetic lubricant plus one 4 oz bottle of the GM limited slip conditioner. GM powertrain wants to allow for about 300 miles for the conditioner to completely mix with the synthetic lubricant.
Thread Starter
Race Director
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From: Bay Shore, NY 11706 MILD2WILD (M2W)
St. Jude Donor '06-'07
Originally Posted by calemasters
GM powertrain wants to allow for about 300 miles for the conditioner to completely mix with the synthetic lubricant.
Le Mans Master
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From: Thousand Oaks California
Originally Posted by Pipedreams
Thanks, you always have the right answer. So if I use Royal Purple that has the conditioner all ready in the mix the 300 is not needed.
I know, it is tough having to take it easy for a while. The 500 mile break in period was a killer.
Last edited by calemasters; Apr 21, 2006 at 10:16 PM.
Instructor
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From: Dover NH
Originally Posted by calemasters
Ed, The Z06 has the differential cooler, not the Z51. The service manual is generic.
As for the 300 mile rule, when the differential lub is changed, the service manual recomments the GM 75w-90 synthetic lubricant plus one 4 oz bottle of the GM limited slip conditioner. GM powertrain wants to allow for about 300 miles for the conditioner to completely mix with the synthetic lubricant.
As for the 300 mile rule, when the differential lub is changed, the service manual recomments the GM 75w-90 synthetic lubricant plus one 4 oz bottle of the GM limited slip conditioner. GM powertrain wants to allow for about 300 miles for the conditioner to completely mix with the synthetic lubricant.
Add the limited slip conditioner. makes a big difference.
Thread Starter
Race Director
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From: Bay Shore, NY 11706 MILD2WILD (M2W)
St. Jude Donor '06-'07
Originally Posted by LS WON
Use Redline oils you won't have this problem.
