Steve439

I found this over on the Chevelle Forum. I think I might have GL5
rated oil in my 67 trans so I'm going to change it to Redline MT-90...
I already use diesel motor oil as Duke suggests.

!!!!all Muncie Owners Must Read This!!!!

--------------------------------------------------------------------

GUYS/GAL'S?,I know this is the wrong forum for this but i am trying to get the word out to ALL T/C's that run muncie's about this info i just learned that i am sure others are not aware of either.

I was not aware the GL5 & Hypoid additives that contains sulphur & is very slick was harmfull to the syncros in our muncie's that are rated for GL4 80/90 LUBE ONLY. I was unknowingly running GL5 lube in my muncie for 4+ yrs and it has been shifting harder even though clutch is adj correctly. Now i know why after reading the info from the Redline Oil Site which i have LISTED BELOW FOR YOU ALL TO READ TO AVOID DAMAGE TO YOUR MUNCIE'S.

Also,i checked approx 9 auto parts stores in my area and not one of them sells or stocks any 80/90 std trans lube that not rated for GL5/Hypoid,they are all rated for GL5/hypoid use . None of the 9 stores i checked stock the lower rated GL4 80/90 lube thats rated for our older muncie std trans so beware of this as i am sure many of you are running the wrong GL5 rated lube that will eventually tear up your syncro's AND DONT EVEN KNOW IT'S HAPPENING.

I just drilled and tapped my muncie for a drain plug so i could drain the wrong GL5 lube out and replaced it with redilnes MT-90 gearlube thats specifically desigend for our trans but i think it's too late for me but i hope i can save some of your trany's if you take the time to read this great info from Redline oils listed below.

So PLEASE READ THE INFO I HAVE LISTED BELOW FROM THE REDLINE OIL SITE and let me know what you know think and know about this. Please also read the little tid bit of motor oil info i listed below the Redline oil info if you want to help avoid a flat tappet cam failure.

Thanks....Scott


REDLINE Synthetic Manual Transmission Lubricants

GEAR AND SYNCHRONIZER WEAR PROTECTION
Most manufacturers of manual transmissions and
transaxles recommend an 80W or 90W GL-4 lubricant.
GL-5 gears oils which are required in hypoid differentials
are not used in most synchromesh transmissions
because the chemicals used to provide the extreme
pressure protection can be corrosive to synchronizers,
which are commonly made of brass or bronze. Typically,
the use of a GL-5 lubricant in a synchromesh
transmission will shorten the synchronizer life by one
half. The extreme pressure requirements of spur gears
and helical gears found in transmissions are not nearly
as great as found in rear-wheel drive differentials. A
GL-4 lubricant provides adequate protection for most
manual transmissions, unless a unique design
consideration requires the extra protection of a GL-5.
The reason that many manufacturers have made
recommendations of motor oils or ATFs is that petroleum
80W gear oils frequently do not shift well at low
temperatures. Motor oils and ATFs are much more fluid
at lower temperatures and they are not corrosive toward
synchros, but they provide very poor gear protection.
These lubricants provide almost no extreme-pressure
protection. In addition, petroleum multigrade motor oils
and ATFs have very poor shear stability. The shearing
action by a manual transmission on thickeners is much
worse than in an engine or automatic transmission.
Within 5,000 miles the thickeners can be rendered
ineffective and the transmission will be operating on a
much reduced level of protection, as shown in the graph
below. In hot weather these transmissions will whine
and rattle because of poor vibration dampening and
metal contact. Red Line MTL and MT-90 provide the
excellent gear protection of a GL-4 gear oil in a synthetic
lubricant which spans hot and cold temperatures and will
not shear or oxidize with use.

DIRECTIONS FOR USE
Red Line MTL may be used in transmissions which
recommend 75W, 80W, or 85W GL-4 gear oils, or SAE
30 or 5W/10W30 motor oils. If a 90W GL-4 or SAE 40,
10W40, or 15W40 is required, MT-90 may be used. If the
transmission or transaxle requires an SAE 90 GL-5 gear
oil, then Red Line 75W90NS or 75W140NS Gear Oil
may be used. In transmissions which recommend Dexron
or Mercon fluids we recommend our D4 ATF which is
very similar to the MTL, being a GL-4 Gear Oil also. The
D4 ATF will provide better low-temperature shiftability,
and the MTL would provide better wear protection for
racing use. MTL is not designed for use in rear-wheel
drive differentials. Those generally require a GL-5 lubricant
such as Red Line 75W90 Gear Oil. It is not necessary
to flush the transmission before replacing with MTL.
Remove the drain plug and drain while warm. Seal
compatibility has been designed to be similar to petroleum
lubricants, and leakage should be no greater than
any other oil of comparable viscosity. Being formulated
with extremely stable synthetic basestocks, MTL and
MT-90 will last much longer than conventional petroleum
lubricants. However, we do not recommend extended
drain intervals, since without a filtration system, there is
no way to remove metal shavings other than draining the
lubricant. The regular maintenance intervals are also
recommended to insure that the proper level of the fluid
is maintained.


Red Line Oil's MTL and MT-90 are designed to provide excellent protection and improved shiftability for manual transmissions and transaxles, having cured the problem of hard shifting in thousands of transmissions with shifting troubles. How? They have the appropriate coefficient of friction for most manual transmission synchronizers (many gear oils, engine oils, and ATFs are too slippery for proper synchro engagement). And, the wide viscosity of MTL and MT-90 allow proper shifting over the entire temperature range which the transmission will experience. The synthetic base oils used have a very high viscosity index which provides relatively constant viscosity as temperature changes. MTL is a low 70W at very low temperatures and a high 80W, nearly an 85W, at elevated temperatures, providing adequate viscosity to prevent wear and deaden gear noise. MT-90 is a thicker 75W90 version of MTL. The shear stability and oxidation stability of these products are excellent, thus the physical characteristics of Red Line MTL and MT-90 will change little with use.

MTL
MT-90

The MT-90 is a 75W90 GL-4 Gear Oil that’s slightly heavier than MTL. Provides excellent protection of gears and synchronizers and its balanced slipperiness provides a perfect coefficient of friction, allowing easier shifting.


RED LINE SYNTHETIC OIL CORP.
6100 Egret Court
Benicia, CA 94510
(707) 745-6100
www.redlineoil.com

======================================== ========== =======
!!!! F.Y.I./MUST READ BELOW/VERY IMPORTANT/ANTI WEAR ADDITIVES REMOVED FROM 99% 0F ALL MOTOR OILS !!!!

Gee,this is trany oil thing is just like when the oil industry recently removed all the anti wear additives like Zinc from 99% of the motor oils which i am sure is a significant factor in the rising amount of flat tappet cam/lifter fails we are seeing in this site .

Only the valvaline 20W-50 RACING OIL and most 15W-40 DESIEL(sp?)/BIG RIG OILS LIKE SHELL ROTELLA-T,VALVALINE PREMIUNM BLUE,MOBIL DELO,AND CASTROL'S BIG RIG OIL STILL HAVE THE ZINC ANITWEAR ADDITIVES IN THEM TO BETTER PROTECT THE BIG RIG MOTORS DUE TO THE EXTREEM LOADS PALCED ON THE MOTORS PULLING HEAVY LOADS UP HILL FOR MILES ON END.

The zinc/anti wear additives were removed from the motor oils because it could prematurly clog cat converters and also because motors now run roller lifters with much less wear issues and or overhead cams with much better oiling so the Zinc/anti wear additives were deleted.

Just to be safe i contacted shell motor oil division Engineers and they said their rotellea -t 15w-40 big rig diesel oil would be perfect for our older flat tappet camed enginges of the 60's & 70's and also stated that any 15w-40 diesel big rig rated oil would be good to better protect our cams/lifters.

Let me know what you guys/gal's think of this info.

Scott

http://www.chevelles.com/forums/showthread.php?t=132531

SWCDuke

Here we go again - more myths and misinformation - the sky isn't falling!

The orignal transmission oil spec for BW T-10s and Muncies is MIL-L-2105D. Of course, since I'm such a dumb sh... you might actually want to look in your owner's manual or appropriate servince manual to be sure. (What a novel idea! Anyone ever try that before?)

The current commerical equivalent to MIL-L-2105D is 80W-90 GL-5. (Check with the API if you want to verify this statement.)

GL-5 IS WHAT YOU'RE SUPPOSED TO USE!!!

Notwithstanding Redline's warnings about GL-5, when I asked them several years ago if it would be adviseable to use MT-90 (which is a GL-4 spec oil) in a vintage four-speed, they said NO, use GL-5.

Duh!!!!!!!!!!!!!!!!!!!!!!!!!!

Duke

ctjackster

welcome back Duke, we missed ya!

and you stopped in just in time to swat down this ol chestnut that comes around every so often . . .

C64BOB

GL-4, GL-12 whatever. Redline MTL really improves the shiftability of Muncies particularly when cold. Since I pound the stuffing out of my car(s) and have never had issues I really recommend the stuff. MTL is in ever manual gearbox I own except the C6 and that will change over the weekend.

2toys

Have been running Mobil 1 full synthetic gear lube in my '65 M20Cr have had no issues and don't expect any. My .02

Steve439

Hi Duke

Thanks for the reply! My 66 manual says MIL-L-2105B. Is that the
same as MIL-L-2105D? Hopefully yes, it'll save me time and money
to just leave my tranny alone...

SWCDuke

My '63 Shop Manual also lists B, but I think 2105 has seen a couple of revs in the last 40 years - whatever - the current commercial spec is 80W-90 GL-5.

Same with Powerglide. You won't find any Type A Suffix A ATF around, so you use the modern equivalent - Dexron III.

There were no commercial gear lube (GL) specs backs then so GM just used the milspec.

More info at www.api.org is anyone really is interested.

Nothwithstanding the above, it's not a bad idea to change the gearbox oil... oh, say at least every 40 years whether it needs it or not.

SPLITRAY

As soon as I started reading the Redline stuff, I said HMmmm...where's Duke when you needem!!!
Glad to see you're keeping an eye on us!

Steve439

Cool, thanks Duke!

I'm not a member of the Chevelle Forum so I can't update them...
It's actually a sticky thread so a lot of people may be misled.

Geek's 65

Great to see you back Duke. You were sorely missed and sagely quoted on more than one occassion.

Geek

mikem350

Anybody want to add some ZDDP (zinc + phosphorus) anti-wear protection to their oils? Good ole STP (blue bottle) sez it has "more ZDDP than the others" on the label!!!

OldDog58Vette

There's oil in there??

mrg

Interesting .. Can't help but think Redline's self serving plug on their gear oil(s) is a just bit cynical. A 'lil? ..

Duke - good to see you drop in from time to time. ..

63 340HP

The fear of damaging "yellow metals" in transmissions has been going on for a number of years, ever since many factory specifications changed to ATF or synthetic blends. The factory spec changed to address fuel mileage concerns and low temp shift effort, at the expense of noise vibration and harshness (and gear wear - - sometimes).

Take the reasons for a low viscosity lube applied to a B-W or Muncie:

Fuel Mileage (at the expense of gear life)? Not a good answer if the gears are scarce.

Internal rail shift linkages suffer the low temp effort more than external rod linkages, so does this apply? No.

The effort to clutch the synchro's with the more slick GL-5 additives can be a concern. This may be a concern if you choose to apply enough effort to bend shift forks to select your gear (it won't synchronize so I give'r hell til she does). Does this apply to your driving style?

Have you read the NV-3500/4500 reasoning to demand use of only approved lubricants (not GL-5, one myth generator)? This concern needs to be balanced with how much abuse you plan to apply to your cars 40-year old transmission. How important is a 100,000 mile warranty life criteria to your 40-year old vehicle?

Modern transmissions take considerably more pressure on the gears than our older designs, as many need to resist the high torque demands of modern diesel engines. The torque limitation with many of the newer gear sets is fatigue of the gear face, but the torque limit with the Muncie was case distortion due to thrust loading from the gear pitch (why the M22 torque rating is superior). Under normal & extreme service the case will fail (wear & distort) before the gears, and the brass synchro rings are consumable (by design, but over many, many, many miles of service).

You can try to beat the oil company Engineers understanding of your transmissions needs, and blend your own lube with a mix (ATF, STP, EP additives: ZZDP, moly, graphite, etc.) using dyno or synthetic base stock. I have successfully used many blends in off-road endurance racing, but don't let myth be your guide (and know the risk is yours to shoulder if something fails). The guidance needed to make an informed decision on where to improve an over the counter lubricant blend is to identify the weakness of the transmission. I cannot imagine someone having a more accurate failure database than that of the oil companies, unless you build your own racing a specific transmission application with the obvious failure risk (and is that not what GM did before designing the M22).

drd1vette

Dang Duke,
It's good to hear from you again. JohnZ must have had one heck of a time answering us dummies all by himself.
Hope you'll be a regular again for us. Thanks in advance.
Dan