`90 6speed dextron 3????
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
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From: richardson tx
`90 6speed dextron 3????
i cant remember what i put in the transmission last time. the dealer and the parts store keep saying dextron 3. no mater what i do not remember ever ever putting the red stuff in there. i dont belive them. what oil goes in the `90 6peed transmission? thanks
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
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From: richardson tx
called the dealer with the part number for fluid and he says that there was nowhere on the label of the fluid that states its weight. he did say it was 10 bucks a quart. didnt i use 10w30 the last time?
Race Director
Joined: Sep 2001
Posts: 14,674
Likes: 751
From: NEwhere Ohio
FIll it with the factory fill 5w-30 transmission oil. Do not use 5w-30 motor oil as it doesnt have the right additives in there for transmission use (it will mess up your synchros). There is a pn for it in your owners manual. If you dont have your owners manual hopefully someone else can look it up.
Dextron is for automatic transmissions.
Whatever you do, do NOT use BMW Castrol stuff like zfdoc and some other forum members recommend.
I switched to the BMW Castol stuff and ran into all kinds of problems. I would grind gears on 1-2 upshifts at high RPM. In some cases, I had to abort drag runs because the shift lever would physically not move from 3rd to 4th at high RPM.
I switched back to the factory fill 5w-30 and everything worked fine.
Coincidence? I think not. There is one other member here who had problems with the castrol Bmw stuff. He posted about it about a year to a year and a half ago.
Dextron is for automatic transmissions.
Whatever you do, do NOT use BMW Castrol stuff like zfdoc and some other forum members recommend.
I switched to the BMW Castol stuff and ran into all kinds of problems. I would grind gears on 1-2 upshifts at high RPM. In some cases, I had to abort drag runs because the shift lever would physically not move from 3rd to 4th at high RPM.
I switched back to the factory fill 5w-30 and everything worked fine.
Coincidence? I think not. There is one other member here who had problems with the castrol Bmw stuff. He posted about it about a year to a year and a half ago.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
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From: richardson tx
Originally Posted by dizwiz24
FIll it with the factory fill 5w-30 transmission oil. Do not use 5w-30 motor oil as it doesnt have the right additives in there for transmission use (it will mess up your synchros). There is a pn for it in your owners manual. If you dont have your owners manual hopefully someone else can look it up.
Dextron is for automatic transmissions.
Whatever you do, do NOT use BMW Castrol stuff like zfdoc and some other forum members recommend.
I switched to the BMW Castol stuff and ran into all kinds of problems. I would grind gears on 1-2 upshifts at high RPM. In some cases, I had to abort drag runs because the shift lever would physically not move from 3rd to 4th at high RPM.
I switched back to the factory fill 5w-30 and everything worked fine.
Coincidence? I think not. There is one other member here who had problems with the castrol Bmw stuff. He posted about it about a year to a year and a half ago.
Dextron is for automatic transmissions.
Whatever you do, do NOT use BMW Castrol stuff like zfdoc and some other forum members recommend.
I switched to the BMW Castol stuff and ran into all kinds of problems. I would grind gears on 1-2 upshifts at high RPM. In some cases, I had to abort drag runs because the shift lever would physically not move from 3rd to 4th at high RPM.
I switched back to the factory fill 5w-30 and everything worked fine.
Coincidence? I think not. There is one other member here who had problems with the castrol Bmw stuff. He posted about it about a year to a year and a half ago.
Race Director
Joined: Sep 2001
Posts: 14,674
Likes: 751
From: NEwhere Ohio
tons of bad luck with transmissions and the following other mods I deemed worthless:
-NGK TR55 Iridium spark plugs (spark plugs fouled causing no start situations until plugs were replaceed in the dead of winter)
-MSD Digital 6 Plus (3 units worked for 1-2 weeks than broke, leaving me stranded)
-Optima red top battery (I had 3 red top batteries in a row work for a day or two and then stop. They refused to take a charge either and were 'dead' when tested on Advance Auto Parts battery tester.)
hmmm. what other mods am I leaving out?
-------------------------------------------------------------------
The way I figure it with the castrol stuff....Failure effects analysis:
1. It works fine and provides smoother shifting than stock
2. It gives you the same experience as me, grinded gears, possible premature synchro wear, missed shifts, aborted drag runs
The risks seem too great when compared to the benefits. I wouldnt use it it IMHO.
gmpartsdirect.com has the factory 5w-30 stuff but you have to buy a minimum quantity.
-NGK TR55 Iridium spark plugs (spark plugs fouled causing no start situations until plugs were replaceed in the dead of winter)
-MSD Digital 6 Plus (3 units worked for 1-2 weeks than broke, leaving me stranded)
-Optima red top battery (I had 3 red top batteries in a row work for a day or two and then stop. They refused to take a charge either and were 'dead' when tested on Advance Auto Parts battery tester.)
hmmm. what other mods am I leaving out?
-------------------------------------------------------------------
The way I figure it with the castrol stuff....Failure effects analysis:
1. It works fine and provides smoother shifting than stock
2. It gives you the same experience as me, grinded gears, possible premature synchro wear, missed shifts, aborted drag runs
The risks seem too great when compared to the benefits. I wouldnt use it it IMHO.
gmpartsdirect.com has the factory 5w-30 stuff but you have to buy a minimum quantity.
Le Mans Master
Joined: Jan 2004
Posts: 7,276
Likes: 3
From: Why are there squished peanut butter cups in my underware?
Originally Posted by dizwiz24
Whatever you do, do NOT use BMW Castrol stuff like zfdoc and some other forum members recommend.
But my ZF6 likes it and hasn't had any problems with it.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by dizwiz24
tons of bad luck with transmissions and the following other mods I deemed worthless:
-NGK TR55 Iridium spark plugs (spark plugs fouled causing no start situations until plugs were replaceed in the dead of winter)
-MSD Digital 6 Plus (3 units worked for 1-2 weeks than broke, leaving me stranded)
-Optima red top battery (I had 3 red top batteries in a row work for a day or two and then stop. They refused to take a charge either and were 'dead' when tested on Advance Auto Parts battery tester.)
hmmm. what other mods am I leaving out?
-NGK TR55 Iridium spark plugs (spark plugs fouled causing no start situations until plugs were replaceed in the dead of winter)
-MSD Digital 6 Plus (3 units worked for 1-2 weeks than broke, leaving me stranded)
-Optima red top battery (I had 3 red top batteries in a row work for a day or two and then stop. They refused to take a charge either and were 'dead' when tested on Advance Auto Parts battery tester.)
hmmm. what other mods am I leaving out?
-NGK Iridium... I had these in bastet44s 87 coupe. Worked GREAT. I have Denso Iridiums in mine. Just fine.
-MSD... no experience... don't have it.
-Red top... I have heard they fail...
But jeez... I am glad I don't live near you. Nothing personal, but I have enough bad luck, I don't need yours rubbing off on me!
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Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
Another thing to note is that it is not just ZFDoc and us faceless names on the forum recommending the Castrol fluid...the manufacturer (ZF) also recommends it. They also suggest the GM stuff and some class of ATF that meets their specs.
I will also agree with the Optima red tops...I am on the second one in my 90 and the one in Dad's 86 is on its death-bed.
I will also agree with the Optima red tops...I am on the second one in my 90 and the one in Dad's 86 is on its death-bed.
Race Director
Joined: Dec 2002
Posts: 13,348
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by MATCHLIGHT
I might be wrong on this, but didn't the GM factory fill just get superseded by an Amzoil product?
Larry
code5coupe
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 752
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From: richardson tx
thanks for all the help. i thought i heard something going on around the transmission area and wanted to check the fluid just to be sure it wasnt low. well i went ahead and checked it any way with i would say the car jacked up about 2 1/2 feet on the passenger side. when i unscrewed the filler plug oil came out. seems i must of over fillled it last time. any how i know now that i put 5w-30 motor oil in the last time. i remember thanks to the post by dizwiz24. its been in there for a couple of years. maybe the noise im hearing is cause of it. nah as it turns out the noise was unrelated.