What is a shop that installs shifts kits ? "For Performance "
I've called a few local transmission shops and one
said they don't install them on used transmissions.
And would anyone know if shift kits possibly help
the tranny's lifespan?
I have actually seen what some shift kits have done to a transmissions internal clutches and it's not pretty, so as far as making it last longer I would say no. There are some kits out there that repair some short comings of stock transmissions like weak snap rings or thin clutches and pressure leaks that are just fine to use and can help a tranny last a little longer, but those are usually installed during a transmission rebuild, and that explains why they won't put then in a used transmission without rebuilding it. The best things to do to make your tranny last longer is to service it regularly and put on a good tranny cooler bypassing the one in the radiator, this keeps transmission temps low and prevents fluid from reaching boiling point and burning. HTH
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