Diff Fluid

[RickyBobby]

What grade of diff fluid does everyone use?  I am not looking for brand names.  I have that already figured our based on my new sponsour.  I ran 75W90 last year but was wondering why wouldn't I use 75W140.

[VMS Motorsports]

Depends on how often you change gears. If you're going to run just one gear all season, might as well go with the 75W140, but if you're going to keep changing gears, why bother?

[justfreaky]

http://www.legendsracer.com/index.php?topic=357.0

[RickyBobby]

and how much do you put in?

[VMS Motorsports]

I can't remember the quarts/liters. I was told by the rear end builder to adjust to maximum pinion angle (tilted forward) and fill until it starts coming out the fill hole. That way, you may overfill a little, but there's a breather for that anyway...if you fill it like this he guarantees the rear ends for a year, so I take it as gospel

[RickyBobby]

Thank you.  I was putting in 1 quart as per a fellow racer but I think this may not have been enough.

[JGRacing]

I wrote it down somewhere when I filled mine.  I'll try to find the note.  Dumping fluid in the fill hole until it overflows is how I have done it with everything I have raced and have not had any issues. 

[justfreaky]

Filling the rear end until the lube runs out the hole is the way it is usually done. As for exact amount, I don't know with these rear ends.
You could likely run just a bit less without problems.

JMHO

Steve

[VMS Motorsports]

Key word "likely"

Road course, if you want to cheap out and save $11 bucks go ahead, fluid will slosh back and forth as you turn right and left...oval, a different story. I'd rather spill out a little than burn out a rear end.

Sorry Steve

[justfreaky]

Key word "likely"

Road course, if you want to cheap out and save $11 bucks go ahead, fluid will slosh back and forth as you turn right and left...oval, a different story. I'd rather spill out a little than burn out a rear end.

Sorry Steve

That is a good point Jim!
That is why I said "likely".
With the Mod, I always filled 'till full. Never had rear end issues.

Steve

[JGRacing]

Do they allow the seals on the inside of the axle tubes near the center section?  I do not think there is anything in the rulebook which means probably not, but there are a lot of areas not covered by the rulebook.  The seals are pretty cheap and keep the fluid out of the tubes so the gears cannot run dry in the turns.  

[VMS Motorsports]

The end all be all catch all paragraph...

"If this rulebook does not specifically say that you
can change/modify/add something, then you must
consider that the change/modification/addition is
illegal. Any questions about the legality of a change/
modification/addition not covered in this rulebook,
must be answered by INEX in writing and presented to
the tech inspector upon request. If you have a request for
a change/modification/addition, please contact INEX
before making the change/modification/addition."

 

[Openwheeler37]

I run full synthetic 75w90....but i also get it free from work so I may be a little bias

[thunder938]

Shockproof Lightweight Gear Oil, 75W80, Synthetic...

[apm motorsports]

just  had my gear rebuilt . got hard to turn. The gear guy told me to use redline heavy. put in  1- 1/2 quarts if it does not blow out of over flow add 1/2 more.  I was using 75-90  with only 1 quart in it. Was told not enough.  not racing gears the thicker oil will be better for meshing.   the  heavy is rated 75-245  but acts as 75 -90. Have not raced yet so  do not know about how much should go in gear.