Transmission Longevity 2WD vs. 4WD

Strickly speaking about the 5.3 powered Burbs...model year 2002-2005

I heard that the 4L60E transmissions in the 2WD Burbs are weak and fail sooner than later usually. What about the 2WD/4WD transmissions? Are they the same model number (4L60E) and also are they also likely to not stand up to the test of time?

In other words, am I better off purchasing a 2WD/4WD Burb or just a 2WD Burb in terms of transmission longevity?

Most newer 4L60E transmissions are holding up good.
The 4L80E is the best transmission for HD use.
But with either one proper service is the key to long life transmission.
And most owners manuals say no towing in over drive.

Changing the fluid and filter at least every 50,000 miles is one way of prolonging the life of the 4L60E.Only part I seen break a lot is the sunshell,it breaks or the splines strip out.One thing I do to the 3rd and 4th gear drum if doing a repair or rebuilding it is with the 5 black springs,throw them away.The clutches need to float and it works better.A transmission shop that I know also does this too and that where I heard about this.

Well I'm here at the hospital 140 miles from home ... wife's brother was in a wreck, so I have a lot of time on my hands. Thank goodness for WIFI!

So thanks to Google and thousands of posters I educated myself today on 2WD/4WD and AWD systems and also learned of the GM 4L60E Sun Shell problems.
[ For anyone interested, here is a long thread from '07 on the transmission issue: http://www.gminsidenews.com/forums/showthread.php?t=42520&page=3 ]

One thing I have not found out yet is what year the sun shell design got better...I thought I read 2003, but then I read 2005...

The sun shells seems to be a common point of failure in GM's 4L60E. However, there are a lot of aftermarket "hardened" sun shells on the market that are light years beyond the OEM sun shell. So, you'll want to make sure you always upgrade to the heavier sun shell on every rebuild.

I buy my transmission parts at www.gmtransmissionparts.com

Here is a link to the Beast sun gear:

http://www.gmtransmissionparts.com/The-Beast-Genuine-Aftermarket-Sun-Gear-Shell-w-Washer-4L60E-1011.htm