I would probably say your safe. I ran my stock 28's for about 20 yrs and I punished them pretty hard with various combos. One axle does show some slight twisting, but its been that way for quite some time and hadn't gotten worse. I finally just replaced them last week.
If its an auto it will be more kind to them, along with not getting wheel hop.
My 352 (storked 302) should be pushing 400+ Hp out the rear and I have had no problems with my 9" 28 spline axles with trac loc (I did just recently up graded to 31 Moser axles and a Detroit TrueTrac for future plans at the track).
What you will hear is that if you put slicks on those axles with that motor you might have some proplems in the future (not personal experience, and I don't care to test it).
I ran slicks on my numerous occasions with 500lb feet tq at the wheels. Im sure thats what started the trouble with the one axle. 400hp and 300's tq you should be fine.
I figured the traction lock woudl be fine. Looking at the original axles, i have some surface rust on them. I am betting installing new bearings will be tough over the slightly enlarged axle due to the surface rust. Might try removing some of the rust first to see if bearing will fit.
Car is 5 sp driven on the street.
I just called to have my traction lock rebuilt (figuring it's almost 40 years old, might be time)....600 bucks! How do you know it needs rebuild w/o driving the car? i am tempted to install and drive the car. if its bad, guess i'll now soon enough!
If you have rust on the axles, make sure none of it is on the axle seal area. As far as taking the axle bearings off, it's going to be tough anyway. You definitely need a hydraulic press to do it.
You can't tell if a T-Lok needs a rebuild just by looking at it unless something is obviously broken. There is a torque test for when it's installed in the vehicle that is outlined in the repair manuals. The easy test is to drive the car and do a quick rolling burnout. Two stripes = good T-Lok, one = bad.
Don't forget axles see different torque #'s than the driveshaft. A 4.11 gear puts a lot more stress on the axle than a 3.00. Also a trans with a deep 1st gear can stress the axles more too.
Don't forget axles see different torque #'s than the driveshaft. A 4.11 gear puts a lot more stress on the axle than a 3.00. Also a trans with a deep 1st gear can stress the axles more too.