so confussed on t5 fluid to use.

so confussed on t5 fluid to use.

1984 CJ7

Active Jeeper
1984 CJ-7, 258 (rebuilt), 5 speed (rebuilt), softtop, Goodyear DuraTrac's
I need to change my fluid since i have no idea when it was done last. I have red sooo much on different schools of thought. Gear lube or ATF or syncro.

I will be doing very little off road or non at all. Just driving around town and to the beach. No a daily driver. But, I do want the best for the t5. My CJ 7 is a 1984 with the inline 6. Also, what is the process to change?

My Chiltons doesn't really give a good process for that. I am about 90% sure I have a non-worl class in there.

I went through the same thing with my T-4. I used Mobile 1 ATF with 1 quart of synchromesh. It really smoothed things up.
Looking at the owners manual for my '86 a T5 takes 75w-90 gear oil. From what I have read the earlier CJs stated that it should be atf, but was changed to gear oil in a later supplement. Besides wouldn't you rather run gear oil than atf in a weak tired tranny like a T4 or T5?
I hear that thrown around a lot. What does it mean that the t-4/5 is weak?
Yeah, I think gear oil is what I am going to go with. synthetic gear oil, what weight for syn is the best. I read reagular gear oil would be about 80 weight.
The Borg-Warner T4 and T5 was of a passenger car design and has a cast aluminum housing which is a bad sign. The internals will be O.K. on the street in o.e.m. form, but not when you start making changes to that design, especially when the torque is multiplied thru the transfer case. The later model Wranglers had their transmissions upgraded. Also compared to the other manual transmissions that came in the CJs like the T-176 and the T-18, those weaker transmissions don't look so good.
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Yeah, luckly I plan to only keep mine on the pavement for now. I just want to keep the thing going forward.

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 TRANS 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 Trans and Transfer Case...... or use the AMSOIL MTF. All the Jeep CJ Trans/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 trans shift so NICE!!!! MY T18 -1b granny CJ Trans shift like a very good std trans and not like a truck trans....

STORY OF MY T18 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 trans 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 trans 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 Trans seemed to never have problem.... it as all corrected....

I will also say....
When you trans 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 trans 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 Trans
GL4 is for manual trans & 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 Trans right on the back lable by part number...

WORLD CLASS T4 / T5 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 T4/T5 use gear lube and I would use/recommend the Amsoil MTF

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 Trans 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.
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Thanks MN CJ7, that is pretty good info. I will use the AMSOIL MTF. So, by the sound of it, it will be just fine for the brass syncros.

Best way to enmpy and change would be? Just pull the drain plug, refill until it comes out the fill hole?
yes the Amsoil MTF is for the Jeep Manual Trans/Transf and is not corrosive....

Take a 20 min drive in warmer weather, drain hot. I also use a stick magnet to see if any metal pcs or fillings on the bottom of trans.

Fill up to the fill hole do not need to fill till is spills out, just up to is fine.... Walmart also has a nice plastic adapter for oil containers with a on/off valve that will go ontop of the quart bottles... I use a pc of plastic tubing so its easier to fill up. This way you can let the gear lube gravity feed, or squeeze to help it along..... if you squeeze a lot the Wally valve will leak a bit. Plastic tubing will be close to 1/4" but once you have the Wally World Valve you can buy tubing to fit, like a ft long. Use cardboard on the floor so incase you spill, many times does spill a bit, cardboard will lower the chances of makeing a bit of mess mess with spilled gear lube...

I also put a magnet on the drain plug of trans, transf, engine, and want to put on on the ft/rear pumpkin.... Collects little pcs of metal and also tells you pretty quick if you have isssue/failure?

Glad I could help.... post back after you try the Amsoil MTF
I think you will be impressed!!!

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