4L80E shifting

[65powermonger]

I have a 93 K3500 with 138,000 miles and a fresh trans oil change that sometimes acts like it shifts into netural when shifting from 3rd to 4th. It doesn't do it all the time and it has just started a couple of weeks ago. it other wise shifts fine, shifts are firm. Dumped in some "TransTune" to see if something was "gumed up" and am waiting to see what happens!

Also when you guys tow, do you tow in overdrive or lock it out? I tow an 8x20 inclosed trailer an leave it overdrive. The trans and converter stay locked in unless you have BIG hill then it unlocks. Am i killing my transmission? If i tow in drive, 70mph is about 3300rpm and i'm then killing my engine!

[Chevylover]

I have a 93 K3500 with 138,000 miles and a fresh trans oil change that sometimes acts like it shifts into netural when shifting from 3rd to 4th. It doesn't do it all the time and it has just started a couple of weeks ago. it other wise shifts fine, shifts are firm. Dumped in some "TransTune" to see if something was "gumed up" and am waiting to see what happens!

Also when you guys tow, do you tow in overdrive or lock it out? I tow an 8x20 inclosed trailer an leave it overdrive. The trans and converter stay locked in unless you have BIG hill then it unlocks. Am i killing my transmission? If i tow in drive, 70mph is about 3300rpm and i'm then killing my engine!


My opinion ? If the trans and converter stay locked, it should be no problem. The steady shift from 3rd in OD and back is killing it.

Cu,
Sven