Drivetrain Transmission Fluid Change

GoldenEagle91

Active Member
Dec 25, 2012
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Hi Guys,

It was recommended to me that I swap out the fluid in my T-5 and pop in some new Royal Purple Synchromax. I was told it makes things operate cooler and is better for the gears. I was wondering if anyone has any experience with this in terms of benefits or problems that they experienced after doing a fluid change with this lubricant. The vehicle has almost 90k on it.

Thanks,
Andrew
 
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Its been in my T-5 for many years now. 120K. You need about 3 bottles. Takes a little over 2 and a half. Its all I've run so I can't really compare it to anything else, but I haven't had any issues with the gearbox.
 
Sounds good, currently going into second gear sometimes has issues when the engine is colder. Need to check whether its the level but I may just end up doing the swap because of the good things that I've heard about it.
 
Mobil 1 ATF best hand down over counter fluid, quick and easy to find, Other option is redline, Mobil 1 never fail me.If its good for daily drive 800whp corvett its good for our T5. My best friend mike using mobil 1 aft and mobil 1 oil, and mobil 1 gear oil, and mobil 1 oil filter, on his Z06, he abused that thing and after 5 year it still fine, he sold it before he move to dallas, because his vet wont pass emission in texas.
 
It's unnecessary. Regular, non-Synthetic D3 ATF is all you need.

The T-5 is a pretty good shifting trans. Most shift issues are mechanical by way of clutch adjustment, or damaging the gears through power shifting.

Biggest way fluid affects the T-5 is if the level runs low, or the fluid is too think and the mainshaft bearings starve of lubrication. This is when you get the famous T-5 whine. A brand new T-5 does not make any noise, but the T-5 whine has been accepted my many as "normal". Biggest cause i've found to this is improper fluid level (too low) or wrong fluid (too thick).
 
It's unnecessary. Regular, non-Synthetic D3 ATF is all you need.

The T-5 is a pretty good shifting trans. Most shift issues are mechanical by way of clutch adjustment, or damaging the gears through power shifting.

Biggest way fluid affects the T-5 is if the level runs low, or the fluid is too think and the mainshaft bearings starve of lubrication. This is when you get the famous T-5 whine. A brand new T-5 does not make any noise, but the T-5 whine has been accepted my many as "normal". Biggest cause i've found to this is improper fluid level (too low) or wrong fluid (too thick).

During the winter I had one hell of a time shifting in and out of gears because we were looking at temps of 20 below sometimes and from what I understand synthetic doesnt freeze
 
During the winter I had one hell of a time shifting in and out of gears because we were looking at temps of 20 below sometimes and from what I understand synthetic doesnt freeze

Neither does normal ATF...otherwise every automatic transmission car out there would have issues in cold weather. I've never had an issue with normal ATF in my T-5 in cold weather at all.

Do you know what's in the trans now?
 
how cold is too cold, those southern peoples call 50* is cold lol ( those are wussy ) -5* is not even cold for us. So depend how cold is cold for you lol

I use Mobil 1 because the guy over that build world class T5 for ford that told me to use mobil 1 ATF.

Synthetic will out performing dino regular gear oil/ oil any day of the week over cold weather, end of discussion .
 
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Synthetic will out performing dino regular gear oil/ oil any day of the week over cold weather, end of discussion .

Disagree

The issues with the T-3650 cold-weather 1-2 shift in the 2001-2004 Mustang GT's is a perfect example where the cold weather 1-2 clunk was "fixed" by changing the recommended fluid fill from synthetic to a non-synthetic fluid would allow the synchros to grab and engage better. This change came from Tremec's own engineers. Having owned a 2003 GT, i changed to non-synthetic fluid and it did have a improvement in cold weather shifting.

I won't dispute that synthetic fluids are better, but their use in a manual trans is slightly different when a transmission actually relies on friction to physically slow and engage the spinning gears and lubrication of the various bearings as a secondary concern.

With that said, there are fluids that interact with the various linings of of the blocker rings. Tremec themselves have recommended against using Gm Synchromech is all of their trans other then the 3550. Yes, i know plenty of people use it in a T-5
 
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" One last piece of important information. ALL World Class T-5 use ATF (Dextron III) oil and NOT heavy gear oil or Redline MTL! All NON-World Class T-5 use 50 wt gear oil. (The original Ford/Borg-Warner recommendation back in 1984 was Dextron II. As this is no longer available, we and TREMEC recommend the 50 wt gear oil.) We recommend high quality Synthetic oil as it lasts a long time and over a larger operating temperature. It is important to change the oil in your transmission based on how you use the vehicle. If the vehicle is your daily driver then changing the oil every two to three years is fine. However, if the transmission sees regular track duty and pushed hard, then once or twice a year is in order. When we rebuild transmissions, we can tell when the oil has been changed often as the parts are much cleaner with less over all wear. There is no filter inside the manual transmission only a magnet at the bottom to pick up the metallic particles in the oil, the only metallic parts in a transmission is the gears or bearings. Oil is cheap, transmissions are not! "

After they announce that, we on other forum made a vote and some email from the, and Mobil 1 ATF was came out on top, some even mix mobil 1 ATF + lucas transmission fix and it made their transmission shift much smoother, myself and most other just run straight Mobil 1 ATF

I been using mobil 1 atf on all my mustang manual transmission on cold weather minnesota, I alway let it drive slow on first gear half miles to let fluid warm up, and never have any shifting issue.

Tremec's most recent 3650 service manual says this
Tremec3650OilSpec01.gif
 
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During the winter I had one hell of a time shifting in and out of gears because we were looking at temps of 20 below sometimes and from what I understand synthetic doesnt freeze

You should drive slow on first gear for first 2-3 min when cold weather, that allow the fluid to get a bit warmer and flow better. Because when cold fluid get thicker, with synthetic it flow better in cold , and that allow the oil to get to where it need to be faster then regular dino fluid. This had been proven by many company that spend million dollar on testing and research.

I alway warm up my car 2-3 min on cold weather and 1 min on hot weather, I alway drive slow for first half mile to get tranny, engine oil, rear diff fluid to get a chance to go where it need to go. before banging on it :rlaugh:
 
Do you know what's in the trans now?

No I do not know what is currently in the tranny. My guess would be the original trans fluid but I don't know for certain. I am not the original owner.

'
You should drive slow on first gear for first 2-3 min when cold weather, that allow the fluid to get a bit warmer and flow better. Because when cold fluid get thicker, with synthetic it flow better in cold , and that allow the oil to get to where it need to be faster then regular dino fluid. This had been proven by many company that spend million dollar on testing and research.

I alway warm up my car 2-3 min on cold weather and 1 min on hot weather, I alway drive slow for first half mile to get tranny, engine oil, rear diff fluid to get a chance to go where it need to go.

This past winter I had to warm my car up for about 20 minutes before I could even think about going anywhere with it because it would stumble and then completely fall on its face. Definitely had the learning curve going.
 
how the transmission shift now ? if it have problem, there is no transmission fluid can fix it, it might help but it wont be pernament fix. You can try mobil 1 to see how it shift, but if it grind or wont go into gear, then rebuild need to be done soon.
 
how the transmission shift now ? if it have problem, there is no transmission fluid can fix it, it might help but it wont be pernament fix. You can try mobil 1 to see how it shift, but if it grind or wont go into gear, then rebuild need to be done soon.

The transmission shifts alright. It's just from first to second that can be kind of crumby sometimes. It doesnt grind or anything like that and its more of an issue when its pretty cold. It seems to be getting better now that its warming up but I will adjust the clutch cable at the firewall again to see if that helps any
 
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