Thicker or lighter oil in your center diff and why?
#1
Thread Starter
Tech Adept
Joined: Jun 2012
Posts: 111
From: Southern california
What are the bonuses in running a thicker weight fluid in your center differential? I know like drake runs 5000, 7000, 2000 and i currently run 5000, 5000, 3000 and i have the same clutch setup and engine that he runs. I just don't know what the plusses are to running a tjicker weight in the center. If anyone can elaborate i would appreciate it.
#3
It's really track, surface and driver dependent. Heavier fluid in the center will transfer more power to the rear wheels which can be beneficial on high bite surfaces as well as prevent diffing out (ballooning front tires). It can also cause a loose rear end feel if you have a heavy trigger finger. If you aren't winning or placing in the top 5 in races it isn't because you diff fluids are off. 5/5/3 will work well enough in most circumstances.
Try it out and see what you think.
Try it out and see what you think.
#5
What are the bonuses in running a thicker weight fluid in your center differential? I know like drake runs 5000, 7000, 2000 and i currently run 5000, 5000, 3000 and i have the same clutch setup and engine that he runs. I just don't know what the plusses are to running a tjicker weight in the center. If anyone can elaborate i would appreciate it.
The 30K was just what I needed. No problems with the double and I could not find any negatives to making this change. I also noticed less ballooning of my front tires on the straight.
Lee
#6
A very wise man once wrote this on another forum and it has stuck with me. I have found this to be the best and most accurate explanation of diff oils:
"Keep in mind, that it is also has a lot to do with how you drive, and the design parameters for your car’s platform.
While thinner oil in the rear may make it a little unstable, “unstable” is a subjective word. In this case, “unstable” would mean that the rear end rotates quicker. Pending your driving style, this could be what you’re looking for, and could be described as “stable” to you.
I like a lot of off-power steering and the design of my car tends to push a little, so I run thin (3K) in the front.
I like a softer “punch” during acceleration, and my car’s design carries a lot of traction under acceleration, so I run 4K in the center.
My car has a shorter chassis than some of the newer revisions, so the rear of the car rotates easily and I had to actually go up to a thicker than conventional rear oil (5K) to slow down that rotation.
So, I run 3/4/5……which is somewhat abnormal. But the point is, it suits the design of the and my driving style.
As for a direct answer to your center diff question, think of it as a “punch control” or a “slipper”………….that’s the easiest way I can think of to explain it. The thicker you go in the center, the harder the “hit” from the wheels when you pull the trigger!
And no, thinner oil in the center will not apply more power to the front, it will apply less power to front AND rear. If you want the front to "pull" in the direction you have the wheels turned, go up (thicker) in the front diff. The trade-off is that it may hinder your steering while you're off the power and trying to steer through a slow turn."
Hope this helps!
"Keep in mind, that it is also has a lot to do with how you drive, and the design parameters for your car’s platform.
While thinner oil in the rear may make it a little unstable, “unstable” is a subjective word. In this case, “unstable” would mean that the rear end rotates quicker. Pending your driving style, this could be what you’re looking for, and could be described as “stable” to you.
I like a lot of off-power steering and the design of my car tends to push a little, so I run thin (3K) in the front.
I like a softer “punch” during acceleration, and my car’s design carries a lot of traction under acceleration, so I run 4K in the center.
My car has a shorter chassis than some of the newer revisions, so the rear of the car rotates easily and I had to actually go up to a thicker than conventional rear oil (5K) to slow down that rotation.
So, I run 3/4/5……which is somewhat abnormal. But the point is, it suits the design of the and my driving style.
As for a direct answer to your center diff question, think of it as a “punch control” or a “slipper”………….that’s the easiest way I can think of to explain it. The thicker you go in the center, the harder the “hit” from the wheels when you pull the trigger!
And no, thinner oil in the center will not apply more power to the front, it will apply less power to front AND rear. If you want the front to "pull" in the direction you have the wheels turned, go up (thicker) in the front diff. The trade-off is that it may hinder your steering while you're off the power and trying to steer through a slow turn."
Hope this helps!
#7
A very wise man once wrote this on another forum and it has stuck with me. I have found this to be the best and most accurate explanation of diff oils:
"Keep in mind, that it is also has a lot to do with how you drive, and the design parameters for your car’s platform.
While thinner oil in the rear may make it a little unstable, “unstable” is a subjective word. In this case, “unstable” would mean that the rear end rotates quicker. Pending your driving style, this could be what you’re looking for, and could be described as “stable” to you.
I like a lot of off-power steering and the design of my car tends to push a little, so I run thin (3K) in the front.
I like a softer “punch” during acceleration, and my car’s design carries a lot of traction under acceleration, so I run 4K in the center.
My car has a shorter chassis than some of the newer revisions, so the rear of the car rotates easily and I had to actually go up to a thicker than conventional rear oil (5K) to slow down that rotation.
So, I run 3/4/5……which is somewhat abnormal. But the point is, it suits the design of the and my driving style.
As for a direct answer to your center diff question, think of it as a “punch control” or a “slipper”………….that’s the easiest way I can think of to explain it. The thicker you go in the center, the harder the “hit” from the wheels when you pull the trigger!
And no, thinner oil in the center will not apply more power to the front, it will apply less power to front AND rear. If you want the front to "pull" in the direction you have the wheels turned, go up (thicker) in the front diff. The trade-off is that it may hinder your steering while you're off the power and trying to steer through a slow turn."
Hope this helps!
"Keep in mind, that it is also has a lot to do with how you drive, and the design parameters for your car’s platform.
While thinner oil in the rear may make it a little unstable, “unstable” is a subjective word. In this case, “unstable” would mean that the rear end rotates quicker. Pending your driving style, this could be what you’re looking for, and could be described as “stable” to you.
I like a lot of off-power steering and the design of my car tends to push a little, so I run thin (3K) in the front.
I like a softer “punch” during acceleration, and my car’s design carries a lot of traction under acceleration, so I run 4K in the center.
My car has a shorter chassis than some of the newer revisions, so the rear of the car rotates easily and I had to actually go up to a thicker than conventional rear oil (5K) to slow down that rotation.
So, I run 3/4/5……which is somewhat abnormal. But the point is, it suits the design of the and my driving style.
As for a direct answer to your center diff question, think of it as a “punch control” or a “slipper”………….that’s the easiest way I can think of to explain it. The thicker you go in the center, the harder the “hit” from the wheels when you pull the trigger!
And no, thinner oil in the center will not apply more power to the front, it will apply less power to front AND rear. If you want the front to "pull" in the direction you have the wheels turned, go up (thicker) in the front diff. The trade-off is that it may hinder your steering while you're off the power and trying to steer through a slow turn."
Hope this helps!
#9
I'm playing around with losi's overdrive, only had 2 races on it, trying to get it dialed for spring time here. Think I was to heavy in the front, seemed to push in the tight turns of the track, I was thinking...lighter in the front might help that?
#10
Very well could be, but also keep in mind you can dial out low speed push with ride height, camber link and even center diff adjustments.
#13
Tech Addict
Joined: Jun 2007
Posts: 563
From: Sydney Australia
Centre diff :- the thicker you go the quicker your car will accelerate, at the cost of on power stability.
Basically my rule of thumb is to go as thick as you can until it becomes undriveable and then back it off a couple of K's
Basically my rule of thumb is to go as thick as you can until it becomes undriveable and then back it off a couple of K's
#14
Tech Master
Joined: Jan 2008
Posts: 1,671
#15



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