Originally Posted by TFisher

The busted sun shells seem to be a huge problem with the 4L60E, is there any to prevent this from happening?

Originally Posted by AdamCrosier

The sun shells were designed wrong, so without replacing it, unfortunately no. The spot welds give out and it explodes. Heavy duty sunshells are less than $100.00, but it's a bit of work to replace them. I suppose the fact is this: eventually, it will go. I spoke with one guy when looking into it who had it replaced with a stock unit that then blew within two years. It's a weak spot, there's no maintenance you can do to prevent it, you just have to replace it or deal with it when it explodes. Sadly, there is zero warning. My Blazer has less than 150k (which is a long time for the tranny, evidently) and 95% of it is highway miles. It has had a super easy life, and every single switch, light bulb etc works on it. Then, accelerating up the on ramp to the highway, and BAM.