Hey Guys need advise. My z-28 1995 just out of no where started to leak its transmision oil. My tranny is a 4L60E. When its in parking no oil is observed that leaks but as soon as I put it in gear it leaks out with preasure.

Somesays that its the pump,or converter .

Anyone has any other idea.

 

Up ! Up !

 

GM used an inferior Teflon coated bushing in the 4L60E pumps that would literally fall out of the pump with age. It's due to the bushing design. When this happens, you will leak fluid past the converter seal.
We see many occassions where a customer has just the seal replaced...only to put the trans. back in and still have the same leak. Unfortunately, often times when this bushing comes loose, it will spin in the bore...destroying the pump bushing surface, or even cracking the pump.

Frank
CPT

 

In the 700R4's, they used a "babbit" bushing in the front pump. They were known to spin (weld themselves to the torque converter hub) occasionally, especially when the fluid got hot! This would cause a major front pump leak and it would destroy the pump body. In the early 1990's they introduced the "teflon" bushing to solve this problem, and it did. I have never seen a "teflon" bushing spin, (having torn down hundred's of these units) they fit into the pump body much tighter, and they cause very little wear on the torque converter hub. In 1995-1996 they introduced a "teflon" extension housing bushing, and these were "superior" in their wear qualities, when compared to the "babbit" or the "bronze" bushing, and the wear on the driveshaft yoke was almost non-existent. The leakage at this point was much less if any. Another point is that they will live with very little oil, as compared to the "babbit" or the "bronze" bushing. The "teflon" extension housing bushing can be retro fitted to any TH350, 2004R, & PowerGlide.