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T-5 Fluid

  • Thread starter Thread starter mustanggt5pt0
  • Start date Start date Apr 9, 2007

mustanggt5pt0

New Member
Sep 27, 2004
34
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Cedar Falls, Iowa
Apr 9, 2007
#1
  • Apr 9, 2007
  • #1
T-5's take dexron III ATF correct? And the quantity is in the neighborhood of 3 qts.?
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Apr 9, 2007
#2
  • Apr 9, 2007
  • #2
correct...2.8 quarts or something like that
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Apr 10, 2007
#3
  • Apr 10, 2007
  • #3
It's actually Mercon AFAIK. Same difference but I hate it when folks call our LSD's posi's as well.
 

4G-KDMP

10 Year Member
Jul 23, 2005
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CA
Apr 10, 2007
#4
  • Apr 10, 2007
  • #4
mercon.
 

lutzgt86-91

Founding Member
Feb 20, 2002
88
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0
Homer IL
Apr 10, 2007
#5
  • Apr 10, 2007
  • #5
I use syncromesh in all my t5s
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Apr 10, 2007
#6
  • Apr 10, 2007
  • #6
Synchromesh is recommended for the Tremec TKO transmissions but not the T-5's.
 

mustanggt5pt0

New Member
Sep 27, 2004
34
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Cedar Falls, Iowa
Apr 10, 2007
#7
  • Apr 10, 2007
  • #7
So is it mercon or dexron? Or are those two names interchangeable?
 

bullitstang1313

Member
Jan 21, 2003
713
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Indianapolis / Columbus, Indiana
Apr 10, 2007
#8
  • Apr 10, 2007
  • #8
Mercon
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
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119
Motor City
Apr 10, 2007
#9
  • Apr 10, 2007
  • #9
Just used regular ATF for Ford vehicles. I filled mine with the fill plug out, then when it drains out that hole, wait for it to stop, then put the plug in. I used plain old Valvoline.
 

302RollinHard

New Member
Sep 26, 2005
0
0
0
Columbus, OH
Apr 10, 2007
#10
  • Apr 10, 2007
  • #10
Don't they make dexronIII with mercon. I think that is what I put in mine. Shifts like a dream now.
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
Apr 10, 2007
#11
  • Apr 10, 2007
  • #11
All t5s take mercon dextron III or equivelent.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Apr 10, 2007
#12
  • Apr 10, 2007
  • #12
It seems to me that Mercon is a fluid meeting spec's for Ford, whereas Dexron is GM. It just happens that the characteristics are fairly close between the two, hence their sharing bottles.

Be careful with blanket statements about ATF. Type F, +III, and other ATF's might not be a real hot ticket inside a T5.
 

LASTFOX

Member
Jul 21, 2003
105
0
16
RI
Apr 10, 2007
#13
  • Apr 10, 2007
  • #13
I've used Mobil 1 Synthetic ATF without any problems.
See Here... Mobil 1 Synthetic ATF
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
281
134
Apache Junction, AZ
Apr 10, 2007
#14
  • Apr 10, 2007
  • #14
I was contemplating this the other day when picking up three quarts to change my fluid again this year. I was tempted by that Mobil 1 ATF, but decided on the Hurst Hot Shift fluid. I don't expect it's going to shift any different at all, of course, I just hope it'll hold up a little longer over time than the cheap stuff that might tend to break down a little quicker. Its specifications on the back read for DexIII/Mercon.

Someone slap me if I'm wrong here, but as far as a T-5 goes, the main things to worry about are viscosity and additives. You don't have those teeny-tiny rat-maze passages and whatnot in a T-5 like you do in an AOD, so the useage is a little less complex. You obviously don't want to go pouring 75-140 gear lube in there because it'll be hard as hell to move the shifter and it'll turn to solid snot in winter, but you don't want to run cooking oil in there, either, because you need SOME protection. You also don't want anything weird in there that can react with any of the materials of the internal components. The '94 Probe GT that I had was really anal about specifying ONLY using (IIRC) GL-4 gear fluid in the tranny; using GL-5, which apparently has some kinda sulfur content, would chew up the brass synchro gears in there. So, as long as you stick with any Dexron-III/Mercon equivalent, you should be fine.

On a side-note ... does anyone know if Mercon V is safe to use in a T-5?

I know you can flush the tranny on an AODE or 4R70W and use Mercon V in there to help avoid that whole torque converter shudder problem, and I remember reading that it's either a synthetic blend or a full synthetic. I haven't poured in my Hurst fluid, so if Mercon V's kosher enough to use, I might give that a shot, instead...
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,164
17,860
224
Massachusetts
Apr 10, 2007
#15
  • Apr 10, 2007
  • #15
Darkwriter77 said:
You don't have those teeny-tiny rat-maze passages and whatnot in a T-5 like you do in an AOD, so the useage is a little less complex.
Click to expand...


There are tight areas in the t-5....specifically the needle bearings the gears ride on. They are sort of tough for fluids to get into especially with the gears slinging it outwards.

The biggest killer of t-5's is heat, and heat usually occurs when fluid levels are low or the fluid is too thick (gear oil). The first symptom is the trans will begin to whine as the bearings starve for oil.

Continue and they will score the mainshaft and now your trans will whine more than Fran Drescher.

That is why the Ford engineers chose to use ATF since it's watery enough to reach those tight passages and cool/lube the inner bearings.

Also, synchomesh tends to react with the material in the blocker rings causing slightly faster wear since they will swell a bit. The trans may feel like it shifter better since the enlarged friction material grabs better, but they wear faster. How much is unknown. Instead of going 70K miles on your originals you may now only go 60K or something like that, i don't really know.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
281
134
Apache Junction, AZ
Apr 10, 2007
#16
  • Apr 10, 2007
  • #16
Heh ... my tranny's been whining for the past two years more than my ex-girlfriend.
 
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