I have a rebuilt switch pitch 400 trans I had built almost 9 years ago that hasn't had fluid in it yet. it's in a dry fairly warm garage. am I asking for trouble letting it sit so long before putting it into service?
I would not be at all concerned. I bought a '55 Buick out of a field since the '80's, cranked up and ran good and trans still pulled. Put the trans in my driver and it worked perfectly. Nothing to go wrong from just sitting in the garage.
I wouldn't think so Bob,as long as the seals haven't been wet.I'm hoping so anyway, my dry rebuilt has been sitting for 6 years as well
My 400 for my GSX sat rebuilt and unused for 10 years before I got to install it . Never had a problem . Worked perfectly.
There is a gel that I get my TH400's assembled with,for this reason. I never know exactly when I will use it,and it is just extra insurance against anything drying out.
I would worry most about heat-cool cycles condensing moisture inside. Usually residual oil would protect bearing surfaces; non critical surfaces might show some rust. Don't know about yours, but I would have it wet with a torque converter and an output yoke to seal it better. Bruce Roe
The T-400 in my 53 sat for close to 6 years after having been rebuilt and not used with no problems, it is a VP transmission. The builder plugged all the openings so nothing could get in the transmission while sitting. Bob H.