4L60E filter change, woulda, coulda, shoulda

Changed fluid and filter on 91 OCC. The crossmember interferes with one pan bolt by about 1/2 inch. Therefore, FSM specifies loosening of the transmission mount crossmember and sliding it back about an inch. GM even provided a slotted mount to accomplish this. Luckily, mine isn't too rusted and I was able to unbolt the crossmember. Have to hold nuts on top of frame, not even welded or capture nuts. Also had to support trans on bottle jack.

GM could have easily removed a half inch of the oversized mount plate to make this an easy job. I suppose it's better than newer cars without a pan or dipstick, but it would have been a simple design change.

Technically you have a 4L60... the rotating assembly is nearly identical but the case and valvebody is completely different.

Your bolt point is valid. BTW have you seen my flush instructions via the cooler line as seen on ISSF.

Sherlock9c,

You are correct, mine is a 4L60. The 4L60 was available between 1990 and 1992. Since it's hydraulically controlled, could the 4L60 be mated to an older GM 305, say a boxy, and provide an overdrive?

Yes, under the old nomenclature the 4L60 is known as the TH700-R4, and bolts right on to any 1955-up small block Chevy ;-)

Walterf wrote:

Sherlock9c,

You are correct, mine is a 4L60.  The 4L60 was available between 1990 and 1992.  Since it's hydraulically controlled, could the 4L60 be mated to an older GM 305, say a boxy, and provide an overdrive?

if your looking at giving an old boxy overdrive, it might be easier putting the 2004r automatic overdrive in, as from everything I've read it's a bolt in replacement if the vehicle came with the turbo 350 3 speed auto, to put the 700r4 in worst case you will need to modify both the drive shaft and the transmission crossmember.

Also the 700r4/4l60 is actually vacuum controlled, that's why there's no E, the 4l60E is electronically controlled

[quote="goldwolfnhn"]

Walterf wrote:

Also the 700r4/4l60 is actually vacuum controlled, that's why there's no E, the 4l60E is electronically controlled

The 700R4 and 4L60 line pressure is actually cable controlled via a Throttle Valve (TV) cable. You can install a vacuum modulator on the 4L60E to control line pressure, which was a common mod back in the day. I believe that was mostly done by transmission shops that didn't trust tuners to properly modify the line pressure tables after mods like larger throttle bodies which allowed more torque for a given throttle position. The downside is that they do occasionally break and allow the engine to suck transmission fluid in.