Ok so not an Allison but seeing how I trust this bunch of guys more than any other forum and we have Few Words Mike here why not....lol.
So as some may know but most dont I just got done swapping in a 2001 8.1L (496) into my 1985 Chevy K20 truck. Got that done in January and have been driving here and there since. I had an old tired 350 in it before and left the trans and converter knowing it was going to be on borrowed time. Well that time is here. Trans is still awesome as far as I can tell (think its been built and one time or another before I got it) but tq converter is pissed OFF as of yesterday. Since Ive swapped it it seems super fast and responsive BUT having driven an 8.1L in my HD for past 11 years I know what they are capable of and knew it should be more in this truck being lighter than HD. Always seems like it was dragging ass when hitting gas in high gear (3rd). Yes it kicks down fine when need be too so not that. Thought it was either converter or tcase as it is a 203 as of right now. Also it seems like it took what Id say a bit long to actually "drop" into gear and stop slipping (not actual slipping where rpms go up but normal converter slip).
Fast forward to yesterday when my son says do a burnout turning on to a road and after hitting rev limiter in 1st when manually shifting into 2nd it kills the burnout. Then few miles down road start hearing a noise a son (3 yrs old) says "Daddy that doesnt sound good". No it doesnt...lol. Sounds like a rod is about to let loose but knew it wasnt that. Got under it when got home and sure enough it was coming from converter area for sure. Drove home fine. Not flywheel bolts either and it doesnt appear to be cracked either. Im assuming from everything else and the way its been driving lately its the convertor mainly the stator.
Sooo I have had a TH-475 (yes a 475 3 sp) that I got with a tcase I was wanting last year (NP205). Only paid $300 for both knowing trans needs rebuilt so its a steal even at that.
Question is can I just give this a new converter now and run same trans since it appears to be fine and rebuild the other one at leisure and just swap this new convertor to rebuilt trans or should I just rebuild the 485 now and throw a new convertor on it at same time. Didnt know if the fluids from one would contaminate the other or what.
Also with this being a long bed standard cab 4wd truck that I use for plowing Im thinking about a ACC "Boss Hog" 1600-2200 rpm stall. I dont have any internal engine mods and have long tubes, CIA, EFI Live tuning and some other little stuff. Nothing major. Would imagine at crank its around 400hp and 500tq. Stock cam which is tiny for a BBC. Im currently on 32" tires and 3.73 tires. Will be going to a 35" tire sometime this year.
So do you think that stall will suffice into what Im using this truck for and be ok? Anyone had experience with their products? Ive heard good things from people (friends) about them but I have never used them personally.
Sorry for long post. Trying to be thorough.
Chris
So as some may know but most dont I just got done swapping in a 2001 8.1L (496) into my 1985 Chevy K20 truck. Got that done in January and have been driving here and there since. I had an old tired 350 in it before and left the trans and converter knowing it was going to be on borrowed time. Well that time is here. Trans is still awesome as far as I can tell (think its been built and one time or another before I got it) but tq converter is pissed OFF as of yesterday. Since Ive swapped it it seems super fast and responsive BUT having driven an 8.1L in my HD for past 11 years I know what they are capable of and knew it should be more in this truck being lighter than HD. Always seems like it was dragging ass when hitting gas in high gear (3rd). Yes it kicks down fine when need be too so not that. Thought it was either converter or tcase as it is a 203 as of right now. Also it seems like it took what Id say a bit long to actually "drop" into gear and stop slipping (not actual slipping where rpms go up but normal converter slip).
Fast forward to yesterday when my son says do a burnout turning on to a road and after hitting rev limiter in 1st when manually shifting into 2nd it kills the burnout. Then few miles down road start hearing a noise a son (3 yrs old) says "Daddy that doesnt sound good". No it doesnt...lol. Sounds like a rod is about to let loose but knew it wasnt that. Got under it when got home and sure enough it was coming from converter area for sure. Drove home fine. Not flywheel bolts either and it doesnt appear to be cracked either. Im assuming from everything else and the way its been driving lately its the convertor mainly the stator.
Sooo I have had a TH-475 (yes a 475 3 sp) that I got with a tcase I was wanting last year (NP205). Only paid $300 for both knowing trans needs rebuilt so its a steal even at that.
Question is can I just give this a new converter now and run same trans since it appears to be fine and rebuild the other one at leisure and just swap this new convertor to rebuilt trans or should I just rebuild the 485 now and throw a new convertor on it at same time. Didnt know if the fluids from one would contaminate the other or what.
Also with this being a long bed standard cab 4wd truck that I use for plowing Im thinking about a ACC "Boss Hog" 1600-2200 rpm stall. I dont have any internal engine mods and have long tubes, CIA, EFI Live tuning and some other little stuff. Nothing major. Would imagine at crank its around 400hp and 500tq. Stock cam which is tiny for a BBC. Im currently on 32" tires and 3.73 tires. Will be going to a 35" tire sometime this year.
So do you think that stall will suffice into what Im using this truck for and be ok? Anyone had experience with their products? Ive heard good things from people (friends) about them but I have never used them personally.
Sorry for long post. Trying to be thorough.
Chris
Last edited: