There is a ton of threads on the 48re and the shifting quality but nothing I could find to be specific.
I just had a Goerend converter installed and I already had a trnasgo shift kit done.

Now two things are very evident.
1. All the upshifts are very niticable, I.E. bangy and the 2 to 1 down shift is very noticable when coming to a stop.
2. Under light throttle the tranny shifts 1 to 2 fine but before it shifts to third (at around 40 mph) it first down shifts for half a second, then shifts to third.

Has anyone ran into this sort of thing? The trans shifts fine under some load.

Thanks for any advice,

JR,

 

What you're feeling going into 3rd is probably torque convertor lockup.

As for the hard shifts, that's what you paid for, right?

 

Good point on the hard shifts, but if you look on the side of the TransGo shift kit box, it specifically advertises to improve the quality of the shifts without being "bangy". It wasn't so bad before the TC, but now it's down right annoying. I'm actually considering having it removed. The only tough part is, I had a transmission shop install it, so i'm not really sure what's involved with taking the valve body apart.

And for the pre-third gear shift, down shift, if it was the TC locking up, wouldn't the rpm drop instead of increasing?

 

If you did the shift kit first and drilled the holes for better application of the lockup clutch thats why it is firmer now. The application hits harder with the multi-disk than with the single disk.

The shift to drive under light throttle is one of the problems with the 727/4xR transmissions. What you are feeling is a break away when the band disengages before the direct clutches lock. You have to make some other modifications to the VB and 2nd gear piston to completely get rid of that.

What you are seeing is typical when you address only part of the issues with the transmissions. It just magnifies the other areas that need to be addressed. I am fighting the same problem and still researching what needs to be done to make it work right. the other option is order a Goerends VB designed for your application.

 

I recall from re-installing the VB into the transmission that the plastic piston or plunger that gets sandwiched into place by the valve body, the one that gets the new bigger spring as a part of the shift kit, was very loose when i put it back in.

It was so loose in fact that when i was re-installing the valve body into the trans, this piston would not stay in place on its own. I had to hold it in place with the new spring while positioning the vb in place.

That piston has two gaskets on it, i remember moving it side to side when i put it in place, and it looked like there was way too much play for those seals to be doing their job.

Would leaking transmission fluid pressure past these two seals have something to do with the 2 to 3 shift or the quality of it?

If in fact the transmission shop did drill the VB for firmer engagement, can this be reversed by plugging the holes? I just checked the instructions, and it looks like it can.

I appreciate any input.

JR.

 

If it is leaking by, yes. Thats the accumulator piston and its job is to soften the hit of pressure when the gears changes occur. If it was leaking too bad you wouldn't have any gears at all IIRC. They fit loose at the bottom but tighten up when it gets pushed in by the VB.

 

Mine does the exact same thing and my tranny is bone stock. It has done it since day one.

 

Well, I finally decited to bite the bullet and took my truck in to a local transmission shop to have them look at it. It turned out that the reason behind all my issues is a kickdown cable which was out of adjustment.

I guess if there is not enough slack in the cable, as the transmission downshifts, there would be too much line pressure, causing the bangy downshifts and un-necessary down shifts.

Took the truck for a drive, and it's night and day differance. The shift kit finally is working as intended. This was definately $95 bucks spent very well.

JR.