hi,
Yes there is a ton on this subject.... I will also say many many jeepers put the wrong gear lube in the
Transmission and
Transfer Case ...... ANOTHER FLUID THAT IS BAD FOR OUR JEEPS.... NO KIDDING
I did a lot of research, LOT, the 70s FSMs all say to use GL4, Jeep had some bad recommendations and use GL5 in the early 80s and has a full product line recall and
Transmission were failing left and right.... So there is wrong info in the early 80s FSM, then they used "fish oil" and a Jeep Specific Part Number to fix the situation in the next couple of years...
USE the same NAPA GL4 in the Transmission and Transfer Case ...... or use the AMSOIL MTF. All the Jeep CJ Transmission /Transf from the 60s, 70s, 80s.
NAPA can phone order GL4 in gallons,
and when I first found this 4-5 years ago it $15/gal and is now $25/gallon. So nice of them after I start selling their product and educating JEEPERs & my local Napa Counter they nearly double the price...
AMSOIL has a MTF, manual
Transmission fluid.... ALL I can say OMG, this stuff make your manual
Transmission shift so NICE!!!! MY
T-18 -1b granny CJ
Transmission shift like a very good std
Transmission and not like a truck
Transmission ....
STORY OF MY
T-18 Failing...
Wanted to do pm 6 years or so ago....My 1979 FSM that I use for my 1978
CJ7 (very similar) said to use GL4. I went to 20 places and could not find it. USE what many have the GL5 and in a few months my
Transmission started to fail..... hard 1st, 2nd for normal starts non granny, and reverse, shift for 2nd to 3rd, and any down shifting was getting stiff and felt my
Transmission was failing and need work.... 34,000 orginal miles. Crusty gave me a blurb to try the GL4 at Napa, and showed me the container/mfg..... Well in hours, days, weeks it was better.......... IN 2 months of little use my
Transmission seemed to never have problem.... it as all corrected....
I will also say....
When you
Transmission RATTLES going down the road.... that is your syncros and if you use the right fluid it will GO AWAY..... I cannot imagine how many jeepers are building
Transmission that just need the right fluid...
USE the Amsoi MTF, you will be extremly impressed.... no sht no bll
the price is $9 to 12 qt and many auto stores have it.... MY napa carries here in MN...... TOTALLY SHOCKING HOW WELL IT WORKS....
FSMs also say if you have hard shifting, noisey, and transf does not shift well it may be the wrong fluid...
GL5 is corrosive to yellow metals, copper, phozbronze, brellium copper, brass, etc. Used in syncros and bushings... Has higher levels of sulfur or clorides and / or other cleaning agents... IN ADDITION the lubrication properties are different than GL4 and the GL5 does not have the friction modifers to help the syncros and shift work properly...
GL5 is for pumpkins and not for
Transmission
GL4 is for manual
Transmission &
Transfer Case and not approved for pumpkins...
USE the GL4 then try the AMSOIL MTF you will never go back or change from the AMSOIL.... AMSOIL also lists all our Jeep Manual
Transmission right on the back lable by part number...
WORLD CLASS
T-4 /
T-5 means they use carbon fiber syncros and few minor changes on the gear if memory serves correct. NO jeeps came with world class versions... They are in mustangs. Jeep
T-4 /
T-5 use gear lube and I would use/recommend the Amsoil MTF
NAPA GL4
SAE 85w90 Gear Oil GL4 (also meets GL3)
Part #SL24239
Mfg By Sta-Lube, sibisdary of CRC Industries
Bar Code 72213-24239
$30/gallon, phone order take 1-2 days to arrive, then pick it up, easy
I NOW recommend the Amsoil MTF Manual Transmission Fluid as the best with dozens of tests/feedbacks.....,
NOte... Mobil 1 Synthetic Gear Lubes also tested out well $8-12/quart and is non corrosive.. Valvoline GL5 DYNO Gear Lube is also non corrosive but is a GL5 and getting a Gear Lube that has the right lubrication properties will shift better, another words a GL4 will Shift better than a non corrosive GL5
Bromgarrds Farm Stores, IA, NE, Co, Midwest area also have a GL4 gear lube. Sell 2.5 gal container for like $27.