M6 Gearbox Fill Technique ?
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,380
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From: Life is all about power and control
M6 Gearbox Fill Technique ?
I took my car to a North American motors specialist for a thorough oil change on Friday. It was the first time they had been able to get a thorough look at a C5. We put the car up onto a ramp to have a good look underneath, he was quite pleased with the layout.
When draining the gearbox the mechanic noted that it was canted over at an angle. He undid the temperature sensor/drain plug in order to let the oil drain out faster from the normal drain plug, but found that quite a lot of oil dribbled out from the fil plug hole first. The gearbox was then drained as normal. When refilled with Redline MTL90 it only took about 3.2 quarts which is noticeably less than expected.
Should the car have been raised more on the driver's side in order to level the gearbox and so fill it closer to its nominal capacity ?
When draining the gearbox the mechanic noted that it was canted over at an angle. He undid the temperature sensor/drain plug in order to let the oil drain out faster from the normal drain plug, but found that quite a lot of oil dribbled out from the fil plug hole first. The gearbox was then drained as normal. When refilled with Redline MTL90 it only took about 3.2 quarts which is noticeably less than expected.
Should the car have been raised more on the driver's side in order to level the gearbox and so fill it closer to its nominal capacity ?
Burning Brakes
Joined: Oct 1999
Posts: 1,041
Likes: 0
From: Charleston SC
Re: M6 Gearbox Fill Technique ? (te51cle)
Here is what was just posted on the C5Net:
Changing Transmission Fluid
The refill takes 4 quarts of ATF. The Mobil-1 and Red Line both come in 1 quart bottles. You also need one of those pumps that screw onto the top of the bottle to pump the fluid in from below (they cost about $3 at your auto parts store). The hardest part is getting the car jacked up and on jack stands at an angle where all (or most of) the fluid will drain out. I jacked the front up about 3.5 feet, then jacked the left rear up about 1 foot higher than the right rear (which was nearly on the ground). This angled the car so the drain, at the right rear corner of the tranny, is lowest, and there is a significant down angle from front to rear. Lastly, don’t forget to get the tranny really warm before draining, like drive at 70 mph for about a half hour. Oh, I also installed a magnetic drain plug in the process. That will pick up any ferrous metal chips from the fluid (there shouldn’t be any).
This technique will be especially useful if you want to thoroughly drain the tranny.
Changing Transmission Fluid
The refill takes 4 quarts of ATF. The Mobil-1 and Red Line both come in 1 quart bottles. You also need one of those pumps that screw onto the top of the bottle to pump the fluid in from below (they cost about $3 at your auto parts store). The hardest part is getting the car jacked up and on jack stands at an angle where all (or most of) the fluid will drain out. I jacked the front up about 3.5 feet, then jacked the left rear up about 1 foot higher than the right rear (which was nearly on the ground). This angled the car so the drain, at the right rear corner of the tranny, is lowest, and there is a significant down angle from front to rear. Lastly, don’t forget to get the tranny really warm before draining, like drive at 70 mph for about a half hour. Oh, I also installed a magnetic drain plug in the process. That will pick up any ferrous metal chips from the fluid (there shouldn’t be any).
This technique will be especially useful if you want to thoroughly drain the tranny.
Safety Car
Joined: Sep 2001
Posts: 4,596
Likes: 2
From: Atlanta GA
Re: M6 Gearbox Fill Technique ? (te51cle)
Level drain will require about 3.25 quarts to refill.
Here is a how to that I put together. Thanks to Woosch for hosting it.
http://www.woosch.com/tranny_diff_fluid_change.htm
[Modified by gmblack3, 12:10 PM 1/5/2003]
Here is a how to that I put together. Thanks to Woosch for hosting it.
http://www.woosch.com/tranny_diff_fluid_change.htm
[Modified by gmblack3, 12:10 PM 1/5/2003]
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
Re: M6 Gearbox Fill Technique ? (te51cle)
te51cle,
That's normal. They must overfill them at the factory, mine leaked out the fill plug too. I'm told you can't do a 100% change unless it's a new build, some old oil stays behind.
Is your car a Z06 ? Only Z06's have manual tranmsmission temperature sensor.
That's normal. They must overfill them at the factory, mine leaked out the fill plug too. I'm told you can't do a 100% change unless it's a new build, some old oil stays behind.
Is your car a Z06 ? Only Z06's have manual tranmsmission temperature sensor.
Le Mans Master
Joined: Nov 2000
Posts: 6,266
Likes: 156
From: Galloway Twp. NJ
Cruise-In VII Veteran
Re: M6 Gearbox Fill Technique ? (gmblack3)
I used redline D4 in mine, what is redline MTL90? I hope it's not gear oil!
I bought one of those manual pumps and screwed it onto the redline bottle, worked great!
:cheers:
I bought one of those manual pumps and screwed it onto the redline bottle, worked great!
:cheers:
Thread Starter
Drifting
Joined: Jul 2001
Posts: 1,380
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From: Life is all about power and control
Re: M6 Gearbox Fill Technique ? (George Cooper)
Thanks guys, yes I did warm up the transmission first, it was at about 130F when it was drained. The old ATF that came out looked to be in very good condition but I too put in a magenetic drain plug as cheap insurance.
I chose the MTL90 as from Redline's blurb it looked more suitable than the D4ATF. I do the occasional circuit day and that will put more stress on the transmission. The air temperature has been just below freezing for the last couple of days and shifting from 1st to 2nd is noticeably harder so I'm not sure I made the right choice yet. When the transmission has warmed up shifting seems better than before though.
I have noticed a reduction in noise from the transmission though, unfortunately that's made the noise from the runflats really stand out !
I have an ordinary C5 Coupe not a Z06 but it is definitely fitted with a temperature sensor on the transmission. A difference in spec between UK/export models and US models perhaps ?
I chose the MTL90 as from Redline's blurb it looked more suitable than the D4ATF. I do the occasional circuit day and that will put more stress on the transmission. The air temperature has been just below freezing for the last couple of days and shifting from 1st to 2nd is noticeably harder so I'm not sure I made the right choice yet. When the transmission has warmed up shifting seems better than before though.
I have noticed a reduction in noise from the transmission though, unfortunately that's made the noise from the runflats really stand out !
I have an ordinary C5 Coupe not a Z06 but it is definitely fitted with a temperature sensor on the transmission. A difference in spec between UK/export models and US models perhaps ?
Race Director
Joined: Oct 2002
Posts: 16,477
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From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Re: M6 Gearbox Fill Technique ? (te51cle)
The MT-90 is a gear oil. Older manual transmissions commonly used this, which is why Redline states that as the application for it. It is very unsuitable for the MN6, which uses ATF, a much lighter weight (hydraulic) oil. The harder shifting you noticed is a direct result of that, and I can't tell you the harm it might cause in the future, but I would get it out asap and put the D4 ATF in there.
:cheers:
:cheers:
Thread Starter
Drifting
Joined: Jul 2001
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From: Life is all about power and control
Re: M6 Gearbox Fill Technique ? (Y2Kvert4me)
I'd seen MTL90 (rather than MT90) mentioned by some people before on the forum so I thought I'd give it a try: Factory-fill in the T56 is Dexron III ATF. Red Line D4 Synthetic ATF is a good performance upgrade. If the car is road raced regularly, the best lubricant may be Red Line MTL. It offers better lubrication at high temperature than does automatic transmission fluid. (the quote comes from the Idaho Corvette Page)
The only way to find out if it was the right decision is to leave it in there - I realise it'll hurt my wallet if I'm wrong though ! Hopefully it won't destroy bearings or seals but if anyone has experience of this please chime in !
The only way to find out if it was the right decision is to leave it in there - I realise it'll hurt my wallet if I'm wrong though ! Hopefully it won't destroy bearings or seals but if anyone has experience of this please chime in !
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Le Mans Master
Joined: Feb 2002
Posts: 6,937
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From: Waldorf MD
Re: M6 Gearbox Fill Technique ? (te51cle)
I'm not sure what Redline MTL90 is, but it sure sounds like 90 weight gear oil. The C5 manual transmission takes automatic transmission fluid, as does most modern manual transmissions.
If you use 90 weight gear oil you WILL destroy your sychronizers !
Plus in cold weather, it would be very hard to shift.
And yes, the export models do come with a manual transmission temperature sensor, just like all ZO6s.
[Modified by Oldvetter, 5:03 PM 1/5/2003]
If you use 90 weight gear oil you WILL destroy your sychronizers !
Plus in cold weather, it would be very hard to shift.
And yes, the export models do come with a manual transmission temperature sensor, just like all ZO6s.
[Modified by Oldvetter, 5:03 PM 1/5/2003]
Le Mans Master
Joined: Aug 1999
Posts: 5,411
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From: N Carolina 08 Z51 Coupe
Re: M6 Gearbox Fill Technique ? (Oldvetter)
[QUOTE]I'm not sure what Redline MTL90 is, but it sure sounds like 90 weight gear oil. The C5 manual transmission takes automatic transmission fluid, as does most modern manual transmissions.
If you use 90 weight gear oil you WILL destroy your sychronizers !
Plus in cold weather, it would be very hard to shift.
:iagree: :iagree: :iagree:
If you use 90 weight gear oil you WILL destroy your sychronizers !
Plus in cold weather, it would be very hard to shift.
:iagree: :iagree: :iagree:
Le Mans Master
Joined: Apr 2002
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From: Glendale NY
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16-'17-'18- '19
Re: M6 Gearbox Fill Technique ? (te51cle)
Englishman
I have a 1998 6-speed coupe with 70,000 miles on it. I am due for a tranny rebuild in the near furtute. The syncho's in my trans are starting to go. I could feel a last second "gear lash" changing gears. In the mean time I drained the fluid and added Red Line MTL. I also tried the MTL 90, but thought it was too thick. After using the car for a while, the gear lash all but disappeared. I'm still going to do the tranny, but I was really impressed with the MTL. Go to your Red Line dealer and pick up a bottle of the MTL, read the back of the bottle, I think you might like what you read. For the rearend I use Red Line 75W90. which contains an additive for the limited-slip differential.
Bob NY
:steering:
I have a 1998 6-speed coupe with 70,000 miles on it. I am due for a tranny rebuild in the near furtute. The syncho's in my trans are starting to go. I could feel a last second "gear lash" changing gears. In the mean time I drained the fluid and added Red Line MTL. I also tried the MTL 90, but thought it was too thick. After using the car for a while, the gear lash all but disappeared. I'm still going to do the tranny, but I was really impressed with the MTL. Go to your Red Line dealer and pick up a bottle of the MTL, read the back of the bottle, I think you might like what you read. For the rearend I use Red Line 75W90. which contains an additive for the limited-slip differential.
Bob NY
:steering:
