weld's
Don't want to depress you but 1000's before you and 100's before me have tried this to the same results..... Save up for new main shaft or ask santa!!
The main shaft is very +++ hard ,when you apply heat you remove what in that area?? I have seen many shafts that have had weld's tryed,if the heat wasnd cranked up the weld stuck to the nut only, but the ones that didnt back off the shaft will shear in two like some cut it with a laser. DO NOT WELD...
posted may times ,simple fix, low budget, What ever you want to spend.
And knowing what i know now and did then (oem ) parts can be reused . Also to the other post that split will fail,my test of it aprox 50k loaded 70 % ,also i i will add i drop into 5th level roads around 45 mph empty some time under.
When i talked to mfg some had the thinking that fully spline'd shaft was the cure but my results have but that to bed .
If you cant do the repair your self or don't have a person that will do the work and you can trust By all means order a STD rebuilt. They are good people,I don't agree with the impact use to tighten the nut down with thow... Speed/labor thing.
You don't have to get a new 5 th gear if you don't wish , if it is the first time it came loose. now some out there might not agree But "if" the nut is torqued down and held tight it won't strip.
Parts you will need ,can of starting fluid or break cleen (the good stuf) to clean lube from shaft threads an used/new nut threads. small bottle Red of loc tite. If you have a split nut throw it out.
call std and get the thicker tapered nose nut used by NV "before" the split. . call miller tool and order the adaptor to tighten the nut down with ,3/4 torque wrench fits it the sq--book tells the dealer's they could use blows with hammer and guesstamate 300 lb's Note . if you go with a new 5 th gear you will, even using the eom. main shaft , will have to get/borrow the press or rig one up to install . it is a press fit. and i mean tight. found that out at two in the morning. to rig a press you need a long Gr. 8 threaded rod,long thin wall'd 2" pipe ,1/4 " steel for cap and i used a flange nut. (all were in one corner dust covered ) 2-1/2 - 3 lb hammer
and 3/16 center punch.
! spray down parts to remove lube
2 install 5 th gear
3 apply red loc tite to nut and shaft threads
4 install washer and nut torque to 3--310 Ft Lb's
5 This is what keep's it intact.
I took the cntr punch went up what i thought was t threads tap to dimple then strake a keeper blow --move up a thread repeat--rotate drop down to just on to the nut strike.
Did about ten times----- You have just made a lock nut after instalation... ... ..... Mine has held thru over 4oo k -32k + lbs over the 3 sisters and i only drop out of 5th when the eng call's for 4th.
If you got the transmission on the bench remove the cover and engage 2 gears to hold the shaft..... You will have to tie it down to the bench.
If doing in the truck and you dont want to remove the cover put the shifter in 4th. If you use 1st the eng will roll over .
Note!!! If you have this transmission out and you don't call South Bend Clutch and get there ploit bushing and machine the fly wheel and install Remember i said SHAME on you!!!!