If a D35 is weak then why not lock it?

I have an 8.25 and just installed a no-slip. Powertrax states that the locker actually "strengthens" your rear diff, which getting rid of all that side and spider gear crap will surely do and to which i concur.

So question:
If a locker improves the strength then logically people "should" lock their D35's to enable the rear to handle the action and tire sizes (nothing crazy though) without spending cash on changing the rear.
Just curious about this as i see alot of "it's not worth it to lock the D35" threads.
Makes sense for a DD/Weekend Warrior, no?

Because it increases the stress on the axles which are junk.

Lincoln said:

Because it increases the stress on the axles which are junk.

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... it reduces the stress, specifically driveline windup and abrupt stoppage incurred in open and limited-slip diffs. -Powertrax.

While a locker might remove the "weak spot" found in the spider gears and side gears, they won't do anything about the splines of the shafts - which is actually the weak point.

Now, if you could start by increasing the size of the axle halfshafts, you'd be doing something useful.

However, if you're going to increase the strength in the centre of the axle, you'd not be changing the strength of anything else, but making the halfshafts relatively weaker - which increases the potential of snapping shafts. D35 shafts are damn close to toothpicks, which is why you want to think about changing the axle assembly if you're worried about strength - nearly anything will be better (start by looking for larger axle shafts, taken from the smallest diameter, which is the weakest point. If you can tear it to bits before you take it, inspect the axle shafts for any striations, scratches, or gouges - that's like a line saying "tear here" - a point where stresses concentrate.)

5-90

The problem with the D35 does not lie in the spyder gears...its the toothpicks it uses for axle shafts.

there is no real "fix" for its inherent weakneses but you cannot deny the fact that eliminating wheel spin DOES reduce the potential for breaking a shaft. it wont prevent it. but it will eliminate that specific "weakness".

sidriptide said:

there is no real "fix" for its inherent weakneses but you cannot deny the fact that eliminating wheel spin DOES reduce the potential for breaking a shaft. it wont prevent it. but it will eliminate that specific "weakness".

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Actually, that’s quite the opposite. If you are running an open carrier and one tire hits something solid, the other tire will spin, burning off all of that excess torque. If you are running a locker and one tire hits something solid, both tires are going to try to turn and some thing has to give. Normally the weakest point, which would be one or the other axle shaft.

Lincoln said:

Because it increases the stress on the axles which are junk.

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I guess I'll believe that the day I'm following you around...

on 37's

... you that is.

--ron

Wiley Coyote said:

Actually, that’s quite the opposite. If you are running an open carrier and one tire hits something solid, the other tire will spin, burning off all of that excess torque. If you are running a locker and one tire hits something solid, both tires are going to try to turn and some thing has to give. Normally the weakest point, which would be one or the other axle shaft.

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This, in theory would be true. Except, the spinning shaft would break before the open diff transfers the torque from one shaft to the other. In other words,the spinning, tooth pic, dana 35 axles shafts break before the diff could do its job. Weak dana 35's. Stonger, larger axles shafts are less likely to break as the open diff does its job.

With any axle, when you add a locker it lessens the likely hood of wheel spin but does not change the strength of an axle shaft. After the locker has been added and traction has been lost, then gained abruptly, the wheel that gained the sudden traction is probably the shaft that is going to break. Or, the wheel that has so much traction it wont spin, snap, there goes a shaft.

No, of course it doesn't literally weaken the shaft.
The thing is that an open diff will allow the slip of a non traction wheel moving where as a locked diff will not. Think about it.. How often (for those that are still running 35's...) are you in a situation where BOTH wheels are up against hard traction but you cannot move?

Think of it like this.. You have this force appied to a shaft that is trying to twist but somethig at one end (big rock, etc) won't let it. If you have an open diff then the other side, which either isn't bound at all or is bound to a smaller degree will spin at that point, taking most of the torque/power out of that completely bound up wheel.

Now put a locker into the equation. You have both shafts FORCED to turn at an equal rate, the same power is applied to both shafts. The one that doesn't have much bind will freely spin as it did before. The one that is bound up will be FORCED to spin, if the amount of torque necessary to overcome bind exceeds the amount of torque the shaft is capable of handling the shaft will break.

There is no merit to lockers making axles stronger. Spiders don't break often.

GSequoia said:

No, of course it doesn't literally weaken the shaft.
...There is no merit to lockers making axles stronger. Spiders don't break often.

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Right on! All a locker does is make other weak points become more obvious. Besides the axle shafts, the next weak point in a Dana 35 is the carrier itself (unless you replace it, like with a Detroit), then the axle tube. With that said, I’m running a Dana 35 with a Lock Rite and fully expect to shrapnel it at some point. I guess that would be a good time for me to upgrade to Dana 44s. :laugh3:

Formula for a bulletproof '35....completely gutted truck...nothing inside but seats...no winch...no zillion pounds of bumpers or armor...2.5 power...auto trans....and run 'er in mud only..no rocks...no pavement..no slamming into gear at 6k...no jumps...knowing when to give up and hook up a strap...oh...I did have my axles cryo'd since a buddy has a cryo business and did it for free.

I actually got to watch a UROC competition on TV this weekend...now I know why you need unobtainium everything to survive on rocks.

I have seen several rigs snap (D35) axles....they all did it at the dump of the clutch. maybe i'm just lucky. My MJ is getting a well built 8.8.

boomhauer said:

... it reduces the stress, specifically driveline windup and abrupt stoppage incurred in open and limited-slip diffs. -Powertrax.

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Gotta love Powertrax-bringing the funnay. uke:

Wiley Coyote said:

Actually, that’s quite the opposite. If you are running an open carrier and one tire hits something solid, the other tire will spin, burning off all of that excess torque. If you are running a locker and one tire hits something solid, both tires are going to try to turn and some thing has to give. Normally the weakest point, which would be one or the other axle shaft.

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Actually according to Powertrax, you've got it the opposite...

"Wheel spin-up and abrupt stoppage can cause severe driveline trauma. This occurs easiliy with "open" and "limited-slip" differentials that rush power to a wheel that is slipping or becomes suspended in mid air, even momentarily. When abrubtly stopped by the wheel re-connecting with a high traction surface, the driveline attemps to absorb the extreme shock. Damage to driveline components can occur. Axle shafts may flex, bend or break...The Powertrax No-Slip Traction System gets rid of troublesome wheel spin-up and improves durability and reliability." -Powertrax

Sounds to me like it would increase the chances of NOT breaking the toothpick axles. Ah, but what does Powertrax know.

Can't believe I'm contributing to a discussion about a D35. uke:


You have to consider that when you lift a tire and decrease traction on it with an open it just spins. With a locker it will have all the torque on the shaft with traction. There is where you will find the week spot.

The lunch box may improve the strenth of the spiders but it is also hard on the carrier which is not to great to begin with.

Then you have the issue of the R&P. I have seen a lot of those break. With both tires locked together it gives the ablility to transfer more torque to the ground. That torque has to go thought the R&P.

D35's were ok running open under a stock or close to stock rig. Lock them and/or put large tires on them and they will have problems. Bearings, gears, shafts, everywhere. That is why I try convince people to save their money on locking a D35 and swap in another axle. That $200 or whatever you have to pay for a lunchbox locker is a good step towards something better.

I don't really care for them but I see 8.8 exploder axles for the $350-$500 range all the time. From the factory I've seen 3.27's, 3.55's, 3.73's, and 4.10's. That covers pretty well everything except the stick guys. Money much better spent.

Captain Ron said:

I guess I'll believe that the day I'm following you around...

on 37's

... you that is.

--ron

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I've decided that 35 spline shafts are to much roatating mass. I have a 10 spline D44 with flanged axles in my shed that is dieing to be used. I also have a good tip on a closed knuckle D25 which I'm planning on using because the closed knuckles keep out the walmart grime. Detroit makes lockers for both and that will get me all the strength I need for those 37's.

Men don't need strong axles they just need a p*ssy foot.

come on man - everyone says its crap...

then it must be!

there is no other discussion to be had....

its crap!

Maybe you're right.
Work with me here people, if you have a D35 with both axles locked together, isn't that really the same as having an open D70?
Hell, what's stronger than a D70?

Lincoln said:

Can't believe I'm contributing to a discussion about a D35. uke:

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I can't believe there are people here that actually believe the hilarious psuedo-engineering BS that Powertrax is trying to sell.
To suggest that a locker will lessen the stresses on an axle is just plain funny.
To actually believe them when they say it is just plain sad.

People, think.

Anything, ANYTHING, that aids traction will add stress to the axle components, period.

kid4lyf said:

Anything, ANYTHING, that aids traction will add stress to the axle components, period.

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Damn, the kitty litter just snapped my axle!

Whats stronger than a Dana 70? how about a 40 spline gun drilled ford 9' or Dana 60... hasta

kid4lyf said:

Maybe you're right.
Work with me here people, if you have a D35 with both axles locked together, isn't that really the same as having an open D70?
Hell, what's stronger than a D70?

I can't believe there are people here that actually believe the hilarious psuedo-engineering BS that Powertrax is trying to sell.
To suggest that a locker will lessen the stresses on an axle is just plain funny.
To actually believe them when they say it is just plain sad.

People, think.

Anything, ANYTHING, that aids traction will add stress to the axle components, period.

Click to expand...