I know a couple people people think or have theories about running 4L60/65E transmissions and their variants up into the higher RPM range (6500 +) Saying how some of the parts become starved for oil when the trans is turning that many RPM's... What are your thoughts on this?? I'm shifting mine up at 6800RPM's 1-2 and 6500 2-3.... with my trans and builder I think I'm definitely safe, but I was just wanting to know where you guys stood on the topic

 

ABout the only way for that to happen would be if the pump were to cavitate. I seriously doubt that is an issue. Especially if the unit were to have a deep pan.

The only way I see that happening is if the unit were to not have the proper fill level. I have heard of some people running their units low on fluid intentionally because of fluid pushing out the vent. And of course that is not smart.

g

 

As for the RPM it accurs at that would hard to say and would vary according to fill level and even fluild type viscositys do vary some, But what happens is you come to a place where more fluild is going up into the trans than drains back and uncovers the filter. This is why the 4L60E with the stock shallow pan is so sensitive to fluid level. But even deep pans afermarket such as he dorale with the tubes do nothing to help with this since they still use the short filter. I would never install any deep pan that could not use the deep truck filter which eliminates this concern completely. Now as for not getting enough lube at high RPM if a proper full time lube mod has been made and pump properly prepared and you keep the filter under the fluid there should not be and issue at any RPM as far as adequate lube is concerned . Hope this helps a little info wise.

 

You two guys are the first ones (besides Chuck and/or Vince) I have ever heard say this... I wonder what some other people think as well...


-BTW, I agree with you 100%

 

Now there are other issues involving HI RPM that should be mentioned since you brought tha subject up. 1 is the collapse of the pump slide spring decreasing pump capacity till the volume to low for operation in a performance application, I often think this is in many cases the real cause of the no shift hit the rev limiter 2-3 you hear about so much. This is addressed in any of several ways the sonnax slide spring and in other effective manors I have seen. It was the very reason GM went from one to dual springs here, The early 700r4 and 2004r only had a single spring and when you for instance built them for HI PERF you would get a nice firm shift through about 3/4 throttle and under around 4000 RPM but as soon as the RPM went up the shifts would just slide. I figured that one out early on in my days of building those before they even had shift kits out for them. 2-The centrifical application of the 3-4 clutch in 1st and 2nd gear at high RPM basically what happens here is fluid is pushed against the wall of the 3-4 clutch chamber like the water is held in a bucket when you sling it over your head, This fluid pushes up the wall and forces the 3-4 piston to move up and partially engage the 3-4 clutch causng it to burn and after a while of continually doing it such as a weekend at the track causes the 3-4 clutch to fail. Gm addressed this with the AUX springs that are installed with the 3-4 clutch pack. This is pretty effective actually though if the 3-4 clutch clearance is to high they can hasten a failure also since they limit the travel of the clutch set by design though if the clearance is that high its was going to fail anyway And Transgo addressed it with stiffer 3-4 clutch return springs that are included in the HD2 kit.
Just some info I was thinking after I typed the last one lol