Difficult Decisions
Anyone know the part number on Summit that uses the stock ujoint on the driveshaft?
tail housing off and theres the splines lol so now i need to find the right th400 counterbored slip yoke.
theres the big bolt and his friends.
You will need a 32 spline yoke with a counterbore
The proper way to remedy this is to rebuild the transmission and have the o ring machined off the output shaft, that way you can run a long, full spline, yoke without issue.
I think it's better to run a fully splined yoke like Grady recommends. 91-96 have the lube holes, 97-up don't.
The masters at work on here convinced me to convert to an early lube "hybrid" setup in the late model core so I did the conversion. I'm running the T3-3-5571HP yoke and the 34678R output shaft. The 34678RA shaft that came in my core had to go.
started an initial tear down to inspect the internals while i do the HD2 with the sonnax line to lube valve in the pump, but no drilling or adding the pressure relif plate.
while i was waiting for the new vavle
took out the input shaft and planitary assembly allong with the first set of clutchs and steels. looks like i made a lucky find, it appears to be a reman of some kind. has all stock parts and no drilling modifications.
inputshaft is in good shape. no chew marks on the splines.
planetary looks brand new
pump bushing is still clean, no score marks.
clutchs are still red and have the original grooves
new valve that came in today.
Last edited by JoshuaGrooms83; Aug 4, 2022 at 07:33 PM.
You don't need a fully splined output shaft like 34678R if you machine your existing output shaft. You won't get as much spline engagement, but it will be plenty considering you need at least 0.75" worth of play when installing the driveshaft/yoke onto the output shaft.
I'd just buy the yoke, bottom it out on the machined output shaft, pull it out an inch, measure center of U-joint on the yoke to center of U-joint on the rear end after pulling it out 1 inch from bottoming out, and tell the drive shaft maker to make the driveshaft exactly that long center of U-joint to center of U-joint telling them that the measurement was taken 1 inch from bottoming out on the output shaft.
Last edited by 5.7stroker; Aug 5, 2022 at 08:26 PM.
https://www.dennysdriveshaft.com/p11..._yoke_for.html
got the madman fbody 4l80 dipstick tube. still gotta fine tune the fitting but definitely better than the flex tubes out there.
UMI in for the win with the 4L80 mount and long torqe arm mounting bracket. fits like a glove. they did change the mounting hardware from 10 years ago, so you can use your old poly arm bushing, but youll have to use the supplied hardware from UMI.
the adaptor flexplate is ls to 4l80 setup. wish the bolt holes had some indications built in on it so your not hunting and pecking for the 4l80 holes. the fti 3600 stall fit perfectly.
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