Axle Splines

wal1210 · Aug 13, 2018

I pulled my axle out this weekend so i could change the wheel bearing, drums, and wheel studs and found that my axle splines look to be a little worn. Is this wear normal and are these axles safe to put back or should they be replaced?

Apogee · Aug 13, 2018

I would say that looks pretty normal. No twisting is good, so maybe better than average.

Pa PITT · Aug 13, 2018

... I'm going with Normal also.. They are not twisted & they still have the Etching ..
If you fixed it you'd want to put in 35's then you'd have to swap gear in the sides of your Pumpkin.

Rustytruck · Aug 13, 2018

Do the math on replacing the complete axles. You will probably find using new steel over 50 year old sub par fatigued steel might be the better move.

sprdv1 · Aug 14, 2018

If you abuse it much, may be time for replacement, otherwise should be good for normal use

Apogee · Aug 14, 2018

What's the intended use? Street/trail? Tire size? Gear ratio? Engine/trans? If the end goal is to be able to do some moderate wheeling and not break axles, then I would look at a 31-spline upgrade...but do you have a big-bearing or small-bearing housing? These things tend to snowball, so before you get talked into building a 40-spline trophy truck rear end, let us know what your goals/plans are for the rig.

Broncobowsher · Aug 14, 2018

From what I can see, they look fine. A little wear but still serviceable.

Viperwolf1 · Aug 14, 2018

I'd run it. It looks like you have a limited slip diff in there from the double set of spline engagement.

wal1210 · Aug 14, 2018

The vehicle is a 77 with a large bearing axle. Currently running a 302 and c4. Yes, it does have a limited slip differential from the factory. Ultimately, the vehicle will be mostly a street vehicle with some very light offloading. I've been upgrading little things here and there in an attempt to make it road worthy, although when I have some more time and money, the vehicle will likely undergo a frame off restoration. So, i'm stuck between making it roadworthy now and reusing parts that are not too worn, or shelving the whole project until I can afford to do everything once with upgraded components.

blubuckaroo · Aug 14, 2018

Viperwolf1 said:
I'd run it. It looks like you have a limited slip diff in there from the double set of spline engagement.

Thought the same.
The factory Ford limited slip is really a POS!
It actually uses the first 1/4" of those splines to drive the whole axle.
That's where the failure normally happens. Some call it a broken axle, but it's really just stripped splines.
With an open rear, those splines would last much longer, because they have a full inch of engagement with the spider gears.

Broncobowsher · Aug 14, 2018

Either way, it has been working and by all accounts there is nothing different so it should continue to work just fine for a long time. Parts are not damaged and no reason to expect them to fail in any reasonable amount of time. From the looks of the 40 year old parts, they will last another 80 years before you might want to consider something different.

Viperwolf1 · Aug 14, 2018

blubuckaroo said:
Thought the same.
The factory Ford limited slip is really a POS!
It actually uses the first 1/4" of those splines to drive the whole axle.
That's where the failure normally happens. Some call it a broken axle, but it's really just stripped splines.
With an open rear, those splines would last much longer, because they have a full inch of engagement with the spider gears.

All the factory '77 trac loks I've seen are 4 pinion (4 spider gears). That is a big strength improvement over the earlier 2 spiders. The axles spline to the side gears, not spiders.

blubuckaroo · Aug 16, 2018

Viperwolf1 said:
All the factory '77 trac loks I've seen are 4 pinion (4 spider gears). That is a big strength improvement over the earlier 2 spiders. The axles spline to the side gears, not spiders.

My '77 stripped off the spines and ruined the spider gears at about 80k miles. I was travelling from SOCAL to Transport OR and it died in Redding.
I pulled the rear driveline and drove to Toms (then Ted's 4X4) for a replacement third member and axle.
Toms saved my salmon trip!

sprdv1 · Aug 16, 2018

wal1210 said:
The vehicle is a 77 with a large bearing axle. Currently running a 302 and c4. Yes, it does have a limited slip differential from the factory. Ultimately, the vehicle will be mostly a street vehicle with some very light offloading. I've been upgrading little things here and there in an attempt to make it road worthy, although when I have some more time and money, the vehicle will likely undergo a frame off restoration. So, i'm stuck between making it roadworthy now and reusing parts that are not too worn, or shelving the whole project until I can afford to do everything once with upgraded components.

all a matter of having the time right...

Apogee · Aug 16, 2018

blubuckaroo said:
I was travelling from SOCAL to Transport OR and it died in Redding.
I pulled the rear driveline and drove to Toms (then Ted's 4X4) for a replacement third member and axle.
Toms saved my salmon trip!

Not to hijack the thread, but where in the heck is Transport, OR? Been here my whole life and never heard of it. That said, good job getting over the Siskiyou Pass in front wheel drive...that's a good reason to run a good front shaft IMO.

blubuckaroo · Aug 17, 2018

Uh

Apogee said:
Not to hijack the thread, but where in the heck is Transport, OR? Been here my whole life and never heard of it. That said, good job getting over the Siskiyou Pass in front wheel drive...that's a good reason to run a good front shaft IMO.

Darned phone did that.
I was salmon fishing out of Reedsport OR.
And YES! I feel It's important to keep the front "highway" friendly. What i mean is, It's important to check and correct your front pinion angle after any chassis lift or castor change.

Axle Splines

wal1210

Newbie

Attachments

Apogee

Bronco Guru

Pa PITT

Bronco Guru

Rustytruck

Bronco Guru

sprdv1

REBEL

Apogee

Bronco Guru

Broncobowsher

Total hack

Viperwolf1

electron whisperer

wal1210

Newbie

blubuckaroo

Grease Monkey

Broncobowsher

Total hack

Viperwolf1

electron whisperer

blubuckaroo

Grease Monkey

sprdv1

REBEL

Apogee

Bronco Guru

blubuckaroo

Grease Monkey

Similar threads