Recommendation for trans and primary oils.

badyellowvette

Active Member
You would think this information would be easy to find but I read threads until I was blind without a definitive answer. I know that the primary takes 32oz. and the trans takes 32oz.As far as I can tell ATF (Ford) for the primary and Spectro or Castrol's synthetic 90W140 for the Trans. Is this right or is there better choices? I have to order online because there is nothing available at my local parts stores.
Also do you check the engine oil with the dipstick screwed in or shouldered on the K9, another answer I can't find. Sorry for such rudimentary questions but I just changed my fork oil and want to change the rest my fluids at 1500 miles and don't want to screw it up.
 

woodbutcher

Mr. Old Fart member #145
Staff member
you are right on one count. THE TRANS ONLY TAKES 20 oz.

haven't heard of anybody using Castrol. spectro is now recommended by baker but what was recommended before it was Redline Heavy Shockproof i think 75-140 is the weight but i know the name is right. looks like pepto-bismol.
 
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BWG56

Guru
you are right on one count. THE TRANS ONLY TAKES 20 oz.

haven't heard of anybody using Castrol. spectro is now recommended by baker but what was recommended before it was Redline Heavy Shockproof i think 75-140 is the weight but i know the name is right. looks like pepto-bismol.
X2 I just had my tranny rebuilt by Andy (BigDogTech) today and he sent me packing with Spectro heavy duty 75-140. Great guy and pays alot of attention to detail, would recommend him anytime:2thumbs:

Great to have met you Andy, Thanks again, can't wait to get it back together along with a few more of your tips.

Spectacular turn around time, total of 9hrs to ship, rebuild and return shipment, 16 gallons of petro in the R/T:whoop::whoop:
 

coachk

Active Member
Spectro Platinum HD 75w-140 for the Primary...320z
Spectro Platinum HD Syn for the trans.....20oz
 

woodbutcher

Mr. Old Fart member #145
Staff member
coachK, you sure about the 75-140 for the primary? seems a little too heavy, IMHO, that should be the number for the transmission.
 

coachk

Active Member
coachK, you sure about the 75-140 for the primary? seems a little too heavy, IMHO, that should be the number for the transmission.
That's what I have written down in my service log. I keep track of all the maintenance I do on my K-9.

I'm in Florida where it's always very hot. Before I did the fluid changes, I searched on this site for specs on all fluids and that's what the consensus was. I hope I'm not wrong.

.

.
 

badyellowvette

Active Member
Looks like Spectro is the way to go. Woodbutcher I read in a past thread about using 75w-140 transmission fluid that is where I got the recommendation on the Castrol's synthetic 90W140 and they said it's only the weight of 30w motor oil.
 

bigdogtech01

Well-Known Member
You would think this information would be easy to find but I read threads until I was blind without a definitive answer. I know that the primary takes 32oz. and the trans takes 32oz.As far as I can tell ATF (Ford) for the primary and Spectro or Castrol's synthetic 90W140 for the Trans. Is this right or is there better choices? I have to order online because there is nothing available at my local parts stores.
Also do you check the engine oil with the dipstick screwed in or shouldered on the K9, another answer I can't find. Sorry for such rudimentary questions but I just changed my fork oil and want to change the rest my fluids at 1500 miles and don't want to screw it up.
Like others have said, use only 20-24 oz in transmission, full quart in primary...if you need some Spectro Full Syn 6 spd trans fluid I can send you some. Send me a PM if your interested.
X2 I just had my tranny rebuilt by Andy (BigDogTech) today and he sent me packing with Spectro heavy duty 75-140. Great guy and pays alot of attention to detail, would recommend him anytime:2thumbs:

Great to have met you Andy, Thanks again, can't wait to get it back together along with a few more of your tips.

Spectacular turn around time, total of 9hrs to ship, rebuild and return shipment, 16 gallons of petro in the R/T:whoop::whoop:
Thank you, it was nice meeting you as well. Only 16 gallons? :D
:cheers:
 

coachk

Active Member
Like others have said, use only 20-24 oz in transmission, full quart in primary...if you need some Spectro Full Syn 6 spd trans fluid I can send you some. Send me a PM if your interested.


Thank you, it was nice meeting you as well. Only 16 gallons? :D
:cheers:


Andrew...I have 75w-140 for the primary. Is that not correct?

.
 

badyellowvette

Active Member
Like others have said, use only 20-24 oz in transmission, full quart in primary...if you need some Spectro Full Syn 6 spd trans fluid I can send you some. Send me a PM if your interested.


Thanks Andrew, if I get a solid recommendation on the primary oil I am thinking B&M trick shift, I will order everything from the same place to save on some shipping. I also want to replace my primary gaskets when I change everything.

Any recommendations where to get a gasket Kit?
 
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bigdogtech01

Well-Known Member
Like others have said, use only 20-24 oz in transmission, full quart in primary...if you need some Spectro Full Syn 6 spd trans fluid I can send you some. Send me a PM if your interested.


Thanks Andrew, if I get a solid recommendation on the primary oil I am thinking B&M trick shift, I will order everything from the same place to save on some shipping. I also want to replace my primary gaskets when I change everything.

Any recommendations where to get a gasket Kit?
All parts are from Baker for Primary...I would run the Bel-Ray Primary chaincase lube. $10.95 retail. Spectro Trans fluid $20+ retail.
 

badyellowvette

Active Member
While I have the primary cover off is anyone running a Primary Chain Tensioner? I had a M6 tensioner on my Harley and it worked great.
 

BWG56

Guru
Baker Drivetrain | The Drivetrain Authority

Click on the tab for Baker Factory Support, and go to the bottom, Big Dog service manual. Has all the parts and prices for primary and clutch. I bought the primary kit from them which included the o-ring for the motor, starter,tranny and all the little o-rings for the back of the primary, retaining clips for the bolts, throw out bearing, primary cover 0-ring and the inspection cover gasket for $99.
 
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