Is Reline MTL too thin for our tranny's?
#1
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Is Reline MTL too thin for our tranny's?
I've just changed the transmission fluid in my 83. After I got finished I noticed that the book said to use 90W with temps over 18c. (please no flaming) I did look up to see that I needed 2.1 qts.
I drained my amsoil 75-90 and used redline MTL 70-80, I still have the car up on the rack. Should I drain it out and put the 75-90 amsoil back in it? I've got a friend who has a shop and use his lift, but I forgot the amsoil at home.
This is an ITA car that spends most of its life above 5000 rpm.
Any opinions? Thanks in advance.
I drained my amsoil 75-90 and used redline MTL 70-80, I still have the car up on the rack. Should I drain it out and put the 75-90 amsoil back in it? I've got a friend who has a shop and use his lift, but I forgot the amsoil at home.
This is an ITA car that spends most of its life above 5000 rpm.
Any opinions? Thanks in advance.
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Originally posted by Rx7carl
I doubt theres much difference. Why drain the Amsoil? They are both quality oils, both made from PAO stock.
I doubt theres much difference. Why drain the Amsoil? They are both quality oils, both made from PAO stock.
So that was 6 months a go, I thought I would change it again. I changed the differential lube (with amsoil) than I realized I was a quart short, and happend to have 2 quarts of the MTL.....
I am just concerned about the MTL being less viscous than the amsoil. I running the 4th of July weekend and its going to be hot in College Station. I guess I'll just leave it in and see how it does.
I've been having a problem with some upshits and downshifts. I'm doing the clutch, PP & throw out bearing next week. ALso the shifter bushing. Shifting has gotten very vague and almost went into second a few times instead of third. If that doesen't fix it I guess its time for a rebuild.
Thanks for the reply's.
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Originally posted by inittab
Okay, I'll bite. You use ATF in your manual transmission eh? why?
this should be good
Okay, I'll bite. You use ATF in your manual transmission eh? why?
this should be good
"Red Line MTL is classified as a 75W/80W gear lubricant
satisfying the API Service requirements of GL-3 and
GL-4. MTL also satisfies motor oil viscosities SAE
5W/10W/30, and the viscosity requirements for ATFs.
MT-90 is a 75W90 GL-4 and also satisfies motor oil
viscosities SAE 10W/15W/40. The additive chemistry
used is non-corrosive, so even though they will provide
GL-4 performance, they will not corrode synchros or
bushings. Because of its low corrosivity, Red Line MTL
and MT-90 could also be used in transmissions requiring
GL-1 or GL-3 lubricants. Seal compatibility is designed to
be similar to petroleum-based lubricants."
I can see where you could use it as atf. The stuff is thin. Thus my concern. I'm going to go work on my car this morning. So I'll decide what to do with the trans fluid after I replace my oil cooler lines and bleed the brakes.
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i ran atf in my 83 for a year, it works fine. theres a lot of manual trannies that run atf or gear oil
#10
Old [Sch|F]ool
What I mean is, ATF *works* - there are antifriction compounds in the junk that serve to increase clutch grippage - and synchros are basically just clutches.
Gear oil dowsn't "work", it just sits there being all lubey.
Gear oil dowsn't "work", it just sits there being all lubey.
#11
Old [Sch|F]ool
Additional info:
I knew that gear oil and crankcase oil are rated differently (30 weight gear oil is NOT the same viscosity as 30 weight motor oil) but I couldn't find the chart until now.
Let's see if this works...
(edit: it didn't work, see below)
ATF is about 10-15 weight on the motor oil scale.
75 weight gear oil is about 10-25 weight on the motor oil scale.
80 weight gear oil is about 20-35 weight motor oil scale.
85 is about 30-40 weight on the motor oil scale.
90 is about 40-60 on the motor oil scale.
140 is way beyond, by extrapolation around the 70+ weight motor oil range. (Yes they make 70 weight motor oil! You need it when you are racing with a crappy cast iron crank that can flop around a lot, so you have to run super big clearances in the bottom end, and then you need to run thick sludge for oil to maintain any kind of oil pressure)
I knew that gear oil and crankcase oil are rated differently (30 weight gear oil is NOT the same viscosity as 30 weight motor oil) but I couldn't find the chart until now.
Let's see if this works...
(edit: it didn't work, see below)
ATF is about 10-15 weight on the motor oil scale.
75 weight gear oil is about 10-25 weight on the motor oil scale.
80 weight gear oil is about 20-35 weight motor oil scale.
85 is about 30-40 weight on the motor oil scale.
90 is about 40-60 on the motor oil scale.
140 is way beyond, by extrapolation around the 70+ weight motor oil range. (Yes they make 70 weight motor oil! You need it when you are racing with a crappy cast iron crank that can flop around a lot, so you have to run super big clearances in the bottom end, and then you need to run thick sludge for oil to maintain any kind of oil pressure)
Last edited by peejay; 06-05-04 at 12:56 PM.
#12
Originally posted by peejay
What I mean is, ATF *works* - there are antifriction compounds in the junk that serve to increase clutch grippage - and synchros are basically just clutches.
What I mean is, ATF *works* - there are antifriction compounds in the junk that serve to increase clutch grippage - and synchros are basically just clutches.
So would that be similar to the Redline xx-NS gear oils? Extra stuff to make the syncros work better.
PS Don't you just hate it when oil sits there being all "lubey"?
#13
Old [Sch|F]ool
Originally posted by joeracer
So would that be similar to the Redline xx-NS gear oils? Extra stuff to make the syncros work better.
So would that be similar to the Redline xx-NS gear oils? Extra stuff to make the syncros work better.
That is the method to the madness.
I mean, hmm, Type F (the grippiest of the ATFs) is about $1.19 a quart. MTL is about $8 a quart. Issue resolved.
PS Don't you just hate it when oil sits there being all "lubey"?
#14
I've been using the Amsoil 75W-90 gear oil in my transmissions and rearends for about ten years now and it has never left me wanting for a better product.
It virtually "cured" the skritchy 3rd gear synchro in my RX4 within 6 months, and that's good enough for me.
It virtually "cured" the skritchy 3rd gear synchro in my RX4 within 6 months, and that's good enough for me.
#16
Re: some people also use
Originally posted by DriveFast7
Redline Lightweight Shockproof Diff oil in their manual tranny.
Been itchin' to try that out on the race car.
Redline Lightweight Shockproof Diff oil in their manual tranny.
Been itchin' to try that out on the race car.
-chuck-
#17
Originally posted by peejay
That is the method to the madness.
I mean, hmm, Type F (the grippiest of the ATFs) is about $1.19 a quart. MTL is about $8 a quart. Issue resolved.
Only when it needs to do other things besides lubricate and transfer heat! [/B]
That is the method to the madness.
I mean, hmm, Type F (the grippiest of the ATFs) is about $1.19 a quart. MTL is about $8 a quart. Issue resolved.
Only when it needs to do other things besides lubricate and transfer heat! [/B]
http://www.redlineoil.com/whitePaper/13.pdf
Since changing to a synthetic transmission oil is normally a one time event, I'm not sure saving $20 on the price of the oil is cost effective in the long run.
-chuck-
#20
Old [Sch|F]ool
Originally posted by joeracer
I checked the Redline website. They seem to indicate that ATF doesn't have the shear characteristics needed in a manual transmission.
http://www.redlineoil.com/whitePaper/13.pdf
Since changing to a synthetic transmission oil is normally a one time event, I'm not sure saving $20 on the price of the oil is cost effective in the long run.
-chuck-
I checked the Redline website. They seem to indicate that ATF doesn't have the shear characteristics needed in a manual transmission.
http://www.redlineoil.com/whitePaper/13.pdf
Since changing to a synthetic transmission oil is normally a one time event, I'm not sure saving $20 on the price of the oil is cost effective in the long run.
-chuck-
One time event? I dunno about that... see, lots of people put miles on their cars, and they have to have the tranny out every now and then. Unless you're one of those people who save the old oil and dump it back in again.
#21
Originally posted by peejay
And automatic trannies don't have gears in them?
One time event? I dunno about that... see, lots of people put miles on their cars, and they have to have the tranny out every now and then. Unless you're one of those people who save the old oil and dump it back in again.
And automatic trannies don't have gears in them?
One time event? I dunno about that... see, lots of people put miles on their cars, and they have to have the tranny out every now and then. Unless you're one of those people who save the old oil and dump it back in again.
Save the old oil? No, I think the point I was trying to make was that I'M not the cheap one in this conversation.
My application is racing so my oil gets replaced at least every year, about every 1000 miles.
-chuck-
#22
Blood, Sweat and Rotors
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Re: Re: some people also use
Originally posted by joeracer
I've been using that for a couple of years without serious issue. However, I'm about to try some MTL. I've watched a couple of my competitor's in-car video and they're shifting way faster then I am. I think the Shockproof is too slippery. Redline's website says that Shockproof may cause slower synchro hookup due to slipperiness. They recommend MTL for GL-4 needs and MTL-90 for GL-5 requirements.
-chuck-
I've been using that for a couple of years without serious issue. However, I'm about to try some MTL. I've watched a couple of my competitor's in-car video and they're shifting way faster then I am. I think the Shockproof is too slippery. Redline's website says that Shockproof may cause slower synchro hookup due to slipperiness. They recommend MTL for GL-4 needs and MTL-90 for GL-5 requirements.
-chuck-
Do you think using Redline Light Shockproof Gear oil to slow down synchro actuation would help in my case? Or just exacerbate the problem and start grinding gears?
#23
Re: Re: Re: some people also use
Originally posted by DriveFast7
Hmmm.......interesting. I've had a problem downshifting to 3rd and jamming the trans in 3rd. Just shifting too fast and too hard.
Do you think using Redline Light Shockproof Gear oil to slow down synchro actuation would help in my case? Or just exacerbate the problem and start grinding gears?
Hmmm.......interesting. I've had a problem downshifting to 3rd and jamming the trans in 3rd. Just shifting too fast and too hard.
Do you think using Redline Light Shockproof Gear oil to slow down synchro actuation would help in my case? Or just exacerbate the problem and start grinding gears?
My conclusion is that MTL is probably the best choice. However, DON'T use MTL in your differential. Just as ATF can't handle the pressures in a manual transmission, MTL can't handle the even higher pressures of a differential. They recommend their 75W/90 gear oil for the diff.
-chuck-
#25
Old [Sch|F]ool
Originally posted by joeracer
If you READ the paper I made a reference to, you will see that Redline clearly states that the shear requirements for an automatic are different/lower. Therefore, unless specifically called for by the manufacturer, ATF is not recommended in a manual transmission. They point out that the pressures inside a manual transmission will destroy an ATF within about 5000 miles.
If you READ the paper I made a reference to, you will see that Redline clearly states that the shear requirements for an automatic are different/lower. Therefore, unless specifically called for by the manufacturer, ATF is not recommended in a manual transmission. They point out that the pressures inside a manual transmission will destroy an ATF within about 5000 miles.
B) Pretty much damn near anything will work in a manual tranny, unless of course it's one of the ones that has a pump in it (old Euro overdrive setups, some others?). I like ATF because it shifts a little better and it's cheap, cheaper even than gear oil.