HI again iam thinking about buying a new 4l60 where is the best and cheapest place to get one. and will it hold up in a plow truck. thanks for takeing the time to read and give me your thoughts   gransportw  

For a plow truck I'd be inclined to go with the 4L80-E rather than the lighter-duty 4L60-E. You can buy them at literally hundreds of places, so start checking google. Don't forget that you will need a stand alone controller as well.  

Dirty_Dog:
For a plow truck I'd be inclined to go with the 4L80-E rather than the lighter-duty 4L60-E. You can buy them at literally hundreds of places, so start checking google. Don't forget that you will need a stand alone controller as well.

If this is a a conversion to a 4 speed auto, I would use a 700R4 (a 4L60 is a 700R4 with a electronic valve body) as it requires no computer to work. I have a 700R4 that is 18 years old with 180K miles now and still works fine. The 700R4 has much deeper first gear than a 4L80 too and it is also a few inches shorter too. The only weakness of a 700R4  is heat and when the fail it is because people fry them with big tires and tall gears. See the 700R4 much deeper first gear makes it launch fairly good (better than a 4L80)even with tall ratios but when you get to drive and OD the tranny is lugging with tall gears. Use proper axle gears for tires size and a tranny cooler and a 700R4 will last a long time. If you buy a used 700R4 to rebuilt you want one with a 30 spline input shaft, not one with a 27 spine used from 81 to 84. Bulldog Transmission offers several "flavors" of rebuilt 700R4 with some rated up to 700 HP. One more thing, the deeper first gear and reverse in a 700R4/4L60 vs 4L80 is a plus for plowing snow too  and I have been plowing snow for over 20 years so I know a bit about it and what holds up. If you really want a 4L60, you do not really want a new one rather a rebuilt one that has been upgraded or a 4L65 because the were some drum and sun gear issues with 4L60's from later 90's to about 2005 or so. These developed as they used some cheaper internal parts to cut costs.  

I may be biased against the 4L6x-E because of how many I blew up in my TA before I gave up on them and swapped in a 4L80-E. I don't know about Mad Dog Transmissions, but B&M has a good reputation at the strip.  

That 700R4/4L60 series tranny reached its peak in the 700R4 design. Early 700R4's had 27 spline inputs (81 to 84) and are to be strictly avoided (they can be upgraded to latest standard with a complete overhaul though) The best of the factory 700R4's were built between 87 and 92. When it morphed into the 4L60 GM started using some cheaper stamped parts and the planetary, drum and sprag was prone to fail when abused some. Also you really never want to install a shift kits in a stock 4L60 because it adds stress to these weak parts and leads to failure. GM came out with 4L65 in late 2004 which finally address some of the major problem areas in 4L60 due to the usage of cheaper stamped parts. THose trannies also had lo tolerance to heat and had to be keep cool when working hard (generally 210 or less average temp) if you wanted long life.