T-5 fluid capacity

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You dont really need a pump. Pour it in the top of the shifter hole before you install it. Have the higher up plug on the pass. side of the trans out with a catch pan under it. I top mine off with a 6oz syringe and short hose I got at the auto parts store. They also sell a squeeze bottle for putting fluid up in high places. It has a hose also.
 
I've had my stang for about 13 yrs now and over those yrs I've killed about 15
T-5s. I know this sounds crazy I sure thought it did but the guy who builds my motors told me use 10w30 motor oil instead of ATF and I wouldn't break them so easy. I tried it and I haven't broke one since. That was about 3 yrs ago.He told me the motor oil didn't break down and get thin like the ATF does so it gives the gears a little more cushion. Made me a believer. Just a suggestion. It worked for me
 
The word in a ALL the ref manuals is something about the gear oil not being able to reach all areas of the internal parts.The passages are too narrow and atf can FLOW better to these areas.A friend of mine did the same thing to QUIET his worn t-5.IT worked but when he moved to TX his t-5 took a dump on him on the looong trip!!!
 
NCStang86 said:
I've had my stang for about 13 yrs now and over those yrs I've killed about 15
T-5s. I know this sounds crazy I sure thought it did but the guy who builds my motors told me use 10w30 motor oil instead of ATF and I wouldn't break them so easy. I tried it and I haven't broke one since. That was about 3 yrs ago.He told me the motor oil didn't break down and get thin like the ATF does so it gives the gears a little more cushion. Made me a believer. Just a suggestion. It worked for me

Gear oil isn't thin enough to reach all the tight areas and lubricate the bearings and such. Also, the synchro blocker rings are carbon fiber/paper lined and need to be ATF soaked to work properly. Lack of lubrication (from wrong type or low fluid level) is the cause for noisy, whining gearboxes.

Also, the T5 takes 2.8 quarts, but always fill it til it spills out of top hole. I just fill through shifter while leaving whole open and stop when it comes out. Make sure car is level
 
ill add (for future searchers) that the old school T5's (earlier foxes, Broncos, etc if i remember correctly) do use gear oil (steel synchros, IIRC). Mike probably knows better than I, but it is worth mentioning that the older ones might not take ATF.
 
Mustang5L5 said:
Gear oil isn't thin enough to reach all the tight areas and lubricate the bearings and such. Also, the synchro blocker rings are carbon fiber/paper lined and need to be ATF soaked to work properly. Lack of lubrication (from wrong type or low fluid level) is the cause for noisy, whining gearboxes.

Also, the T5 takes 2.8 quarts, but always fill it til it spills out of top hole. I just fill through shifter while leaving whole open and stop when it comes out. Make sure car is level

He said 10w30 motor oil, not gear oil. Just for clarification. I guess if he says it work then I'm not going to argue with him. My T5 is junk, I might even try it. The synthethit ATF didn't do anything to help it out.


Hissin....I believe you are correct about the older T5's.
 
i have known of a few guys running 10W-30 in their T5, but i would not myself (synthetic ATF will surpass requirements by a mile anyhow, so why take a chance on a fluid that was not designed to go in there).

if wanting to ask someone else, Jason (90MustangGT) used to run 10-30 in his trans before he went with a new TK500, IIRC.

good luck.
 
Yeah , I use 10w30 MOTOR OIL not gear oil. I wouldn't be that crazy and put gear oil in my T-5. I've been running motor oil in my T-5 for about 3 yrs now and haven't had a bit of problem. I drive my car pretty hard everywhere I go and take it on long trips and it shifts like a dream everytime.It don't seem to be as noisy either.
 
Not matter what fluid you use, it's not going to make a difference if you blow the gears. Typically the input shaft blows on a hard launch where it mates the cluster gear or your mainshaft flexes and spreads 3rd gear out causing you to shear the teeth in 3rd. These are mechanical failures that all the magic fluid in the world won't prevent.
 
The following is an excerpt from an article concerning all T5 World Class (WC) trannys used in Mustangs since 1985, from the May 1992 issue of Car Craft magazine written by M. Davis and titled "World Class Act":


"The new synchros are the most significant upgrade. WC 3-4 synchronizers are sintered metal blocking rings that, under high shift force, won't distort as easily as the old brass rings. The WC blocking rings also employ an organic lining on the inner cone surface that mates with the speed gear's cone surface. This lining acts like that of automatic transmission clutch plates, and offers the advantage of more consistent long-term performance, as they suffer less degredation over time. Dexron II automatic trans fluid must be used as a lubricant in T5 WC transmissions because it does not attack the adhesive that holds the organic lining to the blocking rings. Traditional manual trans gear lubricants containing "EP" additives will attack these linings and must not be used."


Personally, I use whatever Ford calls for (in my case it is Mercon ATF). I always use some form of top brand synthetic (currently using Mobil 1). Never had any problems - trans works great. I have no need to deviate from Ford specs.

I also fill the tranny by getting a clear and clean plastic tube and putting it into the top fill hole, and then just funnel the stuff down from above the engine until it starts coming back out of the top fill hole.
 
I wouldn't use synthetic in a manual trans. This may be a case where synthetic may not be better. Synthetics are known for having better lubricating properties than some conventionals, but in a trans that manipulates its synchros with friction, this may not be the case.

Tremec actually for a while recommended it's T-3650 be switched from Synthetic to conventional ATF as a sort of "fix" for the common 1-2 shift grind that trans experiences. The reasoning was the "less-slick" conventional fluid would allow the synchro to grab better and try to aleviate some of the clunk. A lot of people did this, and it worked "enough".

Conventional ATF is more then good enough to lubricate the internals of the T-5. The trans was developed for it and most of us are probably excessive when it comes to maintainence that we would change our fluid well before actually needed anyway.