I am going to be installing my rebuilt 4L60-E tranny next weekend and was curious if there is a break in period like engines.

Do I need to change the fluid after a couple hundred miles?

Is there any advantage to using one brand of fluid over another?

Should synthetic be used?

Thanks in advance.

 

i would stick to regular non-synthetic dexron and no you won't have to change it after a few hundred miles. try no to beat on it for about 500 miles or so. just let it get settled in before you drop the hammer on it.

 

Great, that's the response that I was looking for. I'm using dexron III mercon, & I will be easy on it.

 

Run whatever fluid you plan to use, the breakin period is about 20-30 miles. Make sure you manually shift through the gears (upshift) for the first few miles and recheck the fluid level at about the 20th mile. After this you should be able to make a quarter mile blast.

 

Will do. Thanks for the replies.

 

I romped on mine after about 40 miles. Used a rebuilt kit from Pro Built Autos as well. Working like a charm.