Amsoil:75W90 or 80W90? Experiences? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 07-16-2014, 09:52 AM   #1
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Ottawa, ON, Canada
Posts: 84
Total Cats: 5
Default Amsoil:75W90 or 80W90? Experiences?

Time to switch-out fluids and I'm considering Amsoil products based on the fact that the I started using Rotella T6 based on recommendations here and it's awesome.

Amsoil shows the following for the MSM transmission (not sure if items are listed in order of their recommendation/performance):

Quote:
Manual Transmission,N/A (6-SPD)......GL-5
Above 50 F......80W-90
SAE 80W-90 Synthetic Gear Lube (AGLQT)
SEVERE GEAR 75W-90 Synthetic EP Lubricant (SVGQT)
75W-90 Synthetic Long Life Gear Lube (FGRQT)

Manual Transmission,N/A (6-SPD)......GL-4
Above 50 F......80W-90
Synthetic Manual Transmission and Transaxle Gear Lube (75W-90) API GL-4 (MTGQT)

I've seen recommendations for the GL-4 75W90, but no discussion on the GL-5 80W90. Any experience with it, or technical reasons for not using it? Mazda spec says GL-4 or GL-5 are OK. Any reason to avoid the GL-5?

For the diff, Amsoil shows:

Quote:
Differential, Rear......GL-5
All TEMPS......90
SEVERE GEAR 75W-90 Synthetic EP Lubricant (SVGQT)
75W-90 Synthetic Long Life Gear Lube (FGRQT)
SEVERE GEAR 75W-110 Synthetic EP Lubricant (SVTQT)
SAE 80W-90 Synthetic Gear Lube (AGLQT)
Again, seen recommendations for the SEVERE GEAR, but not discussion of using the 80W90. Any reasons why?

I have to admit, it would be nice to run the same fluid (80W90) in both locations.

Experience, recommendations, thoughts?

Thx.
schmoo is offline   Reply With Quote
Old 07-16-2014, 10:21 AM   #2
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,206
Total Cats: 2,587
Default

I have the former of both in my car now.
Works great. You can see my thread with discussions on both from some smart people if you search.
Can't comment on the latter since neither I nor anyone I know ran it.
18psi is offline   Reply With Quote
Old 07-16-2014, 10:23 AM   #3
Elite Member
iTrader: (8)
 
Join Date: Dec 2008
Location: Kingston, Ontario
Posts: 2,791
Total Cats: 71
Default

I used 75w90 in my Miata trans. it worked really well as far as gear oil goes.

Its not a "quiet" oil by any means, but the gears shifted well. I should mention that the noise could have been the 7lb flywheel and solid hub clutch resonating through the transmission too... just a lot of buzzing from the shifter at high RPM, but again the shifter worked wayyyy better than the oil that was in there... I think it was motomaster 75-90.


I also used a weird 75-90 and sae250 mixture for my diff being that I had a custom build OS Giken. That diff was SO quiet. Would use amsoil on everything again.


You can get a preferred customer card and buy direct on their website. Much cheaper than Canadian tire, but it will take a few days to come from their warehouse in Toronto. The customer card makes sense being that its like $6 or something and will save you more than that on your first purchase.
shlammed is offline   Reply With Quote
Old 07-16-2014, 10:52 AM   #4
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,780
Total Cats: 1,106
Default

I believe Hustler has some old posts about why you need to use a GL-4 oil in the Mazda 6speed.
shuiend is offline   Reply With Quote
Old 07-16-2014, 10:54 AM   #5
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,206
Total Cats: 2,587
Default

Yeah I remember that discussion. OP - do an advanced search on these fluids on here, there have definitely been some seriously awesome discussions on it in the past.
18psi is offline   Reply With Quote
Old 07-16-2014, 11:58 AM   #6
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Ottawa, ON, Canada
Posts: 84
Total Cats: 5
Default

Thx. I shall do further searching.
schmoo is offline   Reply With Quote
Old 07-16-2014, 12:01 PM   #7
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 784
Default

I've always used the 75w-90, MTG in trans, SVG in diff per Savington's recommendations.
concealer404 is offline   Reply With Quote
Old 07-16-2014, 01:15 PM   #8
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Ottawa, ON, Canada
Posts: 84
Total Cats: 5
Default

Found the threads you guys mentioned.

Conclusions:

- Everyone likes Amsoil MTG 75W90; Emilio likes it with some GM Friction Mod added-in
- Motorcraft Full Synth is well regarded with 6-speed (what I've been using), but no UOA data
- With respect to shifting feel, there has been direct comparo between MTG and Motorcraft.
- Hustler is on a crusade to ensure no one puts GL-5 in their gearbox despite the fact that the Mazda manuals say GL-5 is OK for my gearbox (2004 MSM)
- no one has tried the 80W90, which is GL-5

Did I miss anything?
schmoo is offline   Reply With Quote
Old 07-16-2014, 01:19 PM   #9
Elite Member
iTrader: (3)
 
concealer404's Avatar
 
Join Date: Aug 2011
Posts: 8,465
Total Cats: 784
Default

I put MTG 75w90 in our MSM and it was the the ****, the bee's knees, solved world cancer, cured my IBS, and any other awesome thing you can possibly think of.

As an Amsoil dealer myself, i'm directly responsible for at least 100 Miata transmissions being filled with the MTG 75w90 at this point. Done 6 myself. 3 of which were replacing garbage Redline bullshit and every last one i replaced Redline with Amsoil resulted in the car's owner offering me fellatio.
concealer404 is offline   Reply With Quote
Old 07-16-2014, 01:20 PM   #10
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,206
Total Cats: 2,587
Default

Yep, pretty much sums it up.
Just cause a manuf says something is OK doesn't mean its a good idea. Just saying.

You should guinea pig the 80w90 gl5 and report back
18psi is offline   Reply With Quote
Old 07-16-2014, 01:25 PM   #11
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,372
Total Cats: 1,333
Default

GL-5 = renewed virginity
Savington is offline   Reply With Quote
Old 07-16-2014, 01:31 PM   #12
Hug Life
iTrader: (3)
 
Monk's Avatar
 
Join Date: Apr 2014
Location: Huntington, Indiana
Posts: 2,805
Total Cats: 494
Default

Quote:
Originally Posted by Savington View Post
GL-5 = renewed virginity
I should get my wife to try some!
Monk is offline   Reply With Quote
Old 07-17-2014, 10:28 AM   #13
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Ottawa, ON, Canada
Posts: 84
Total Cats: 5
Default

You guys are the biggest bunch of border-line autistic fucktards on the interwebs.

Order & Monies sent to Savington.
schmoo is offline   Reply With Quote
Old 07-17-2014, 01:49 PM   #14
Elite Member
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,479
Total Cats: 116
Default

in an effort to try and find 6 speed high load longevity in a bottle I am now trying

Amsoil SAE 250 Severe Gear GL-5.

seems to shift ok once it warms up a bit. It's thick. Hoping it actually works unlike Redline Heavy shock proof.
bbundy is offline   Reply With Quote
Old 07-17-2014, 06:08 PM   #15
Senior Member
iTrader: (3)
 
Join Date: Dec 2011
Location: Tucson, Az
Posts: 514
Total Cats: 33
Default

Isn't GL-5 not recommended for the Aisin 6-speeds because of yellow metal synchros being damaged by the sulfur additives in GL-5? At least that's why it's not recommended for the 5-speeds. Diff don't care.

Redline Heavy Shockproof is not recommended for any transmissions other than straight cut dog boxes. Their website says no synchro trannies. The stuff is basically a liquid carrier for the lubricating solids.
TheScaryOne is offline   Reply With Quote
Old 07-18-2014, 12:58 AM   #16
Senior Member
iTrader: (1)
 
Join Date: Nov 2010
Posts: 951
Total Cats: -252
Default

MTG FTW
wannafbody is offline   Reply With Quote
Old 07-18-2014, 07:20 PM   #17
Supporting Vendor
iTrader: (3)
 
emilio700's Avatar
 
Join Date: May 2005
Posts: 5,326
Total Cats: 1,347
Default

Quote:
Originally Posted by schmoo View Post
Found the threads you guys mentioned.

Conclusions:

- Everyone likes Amsoil MTG 75W90; Emilio likes it with some GM Friction Mod added-in
Mix of old quotes there. A long while back we used the GM stuff with Redline. We switched to Amsoil MTG (no additives) for transmissions about 4 years ago. For Torsens, Amsoil SVG 75W90 GL-5. For OS Gikens, their proprietary OS250R soup.
emilio700 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
An Old Driver but a newbie in Miata Patriarca Meet and Greet 17 10-13-2015 02:34 PM
Bad head gasket or ? shooterschmidty Engine Performance 8 09-30-2015 11:28 PM
Wilwood Dynapro/dynalite maintenance aidandj Suspension, Brakes, Drivetrain 37 09-28-2015 11:47 AM
Software/IT types/Joe P, step inside please z31maniac Insert BS here 13 09-22-2015 03:59 PM
FS Miatas at MRLS spot PatCleary Local Meets, Events and Tech Days 0 09-15-2015 02:25 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 03:21 AM.