TH400/NP241, sat for 5-6yrs. Rebuild, flush, ???

[muddysub]

So I've dug up my old suburban and I'm starting to restore/modify it. I'll be pulling the engine in the next few weeks and rebuilding it. My question though is concerning the trans and t-case. Having sat without moving since 2005, are they screwed? Should I just pull and rebuild them also? Or will a fluid dump/flush be adequate? They were both rebuilt ~20,000mi before I parked it if that makes a difference.

 

[4X4HIGH]

Chances are the seals in the trans have dried up and will give you issues, the t-case on the other hand should be fine except that you should replace the input and output seals for the same reason but at least there aren't any seals internally that need to be worried about.

 

[muddysub]

****. thats kinda what i was afraid of. i was planning on an SYE for the 241 anyway so that part is ok.

 

[muddysub]

i'm gonna dump the atf out of it this week on my days off and take a look at it. some of the guys at work (ford dealership drivetrain guys) are saying i might be ok as long as no moisture got in there. fortunately it's pretty damn dry here, keeping my fingers crossed.

 

[76zimmer]

my dad has an old DJ-5 and it has an iron powerglide in it that sat for 10+ years. he only had to change the shifter shaft seal, maybe a little wetness around the rear seal, but it don't mark its territory. I'd take a shot at topping it off with new fluid and see what ya got.

 

[folkenheath]

I'd just change all the external seals (converter seal, adaptor seal, tcase input/output etc) and try it. Unless you want piece of mind and a complete resto. As long as the fluid looks good it's probably fine.