I just got thru rebuilding the trans on my '99 4l60E trans that had a bad 2/3 shift. I put the best money can buy as far as I know in it, got a lot of info from in here, I havin a problem with no pump pressure after the rebuild and the front pump is new. Trans go shift kit, been air checked after the pump , all checks out. Replaced the front pump again, still the same thing. Could it be the torque converter or a problem with the valve body? What could I be over looking? At 4 grand the speedo will raise up to about 45 mph and then fall off to 0. I even had a transmission guy look at it and he does not know either. Where could the pressure loss come from? The level in the pan never lowers, I could sure use some advise on this one.

 

Where are the pumps coming from? What all is included? Some pumps don't come with a pressure regulator valve or boost valve. Some don't come with a thimble filter as well and leaving any of these out will cause no pressure.

 

The pump comes with all the parts you listed Tripp, I am sure what ever it is it's prolly simple once I find it. I think the brand new torque converter maybe the reason but I don't know yet.

 

Why did you replace the pump in the first place? Are you using a 300mm converter and matching pump(stator shaft)? Are you verifying no pressure with a pressure gauge?

 

Any chance that the converter wasn't fully seated allowing the pump rotor to become crushed?

 

Tripp, i double checked the convter going into the lugs on the pump and they are ok, I alsi air checked the trans from behind the pump to the rest of the trans and it also checked out ok. I think there is something wrong with the tq.
I am going to search out another converter to replace it with, looking for a 2600 to 3000 stall with a good str.

 

I sell Edge Racing Converters and have yet to hear a single complaint. They are 9.5" converters and are available for LS1 style input shafts.

And let me ask again, are you sure the pumps you are using are specificlly for the 300mm converters?

 

You did put the filter back in? And it is the correct filter for the pan?

 

Everything is back in place. filter is correct for the pan. I don't get it, but still looking.