is my axle strong enough

[klaussk]

So, I have been building a 406" small block  for my 1985 chevy K10 stepside shortbed. It'll have ne double hump heads a mallory unilite headers edelbroke performer and mild cam with a 230 duration at .47 lift( the other specs elude me at this moment for the cam). I have plans to beef up the 700r4 tranny with a better clutch so I think that will hold up just fine. But I'm not sure if the axle will hold or not. I don't even know what axle it has and I'm on deployment  so I can't check. If anyone can shed some light on my issue I would appreciate it. Thank you

[Stewart G Griffin]

It probably has an 8.5" 10 bolt and yes i would say it's strong enough---it's rated for 3,833 ft/lbs. of
 torque.

[Irish_Alley]

its more on how you drive or abuse it. but most upgrade just to have posi

[Stewart G Griffin]

i don't know what the standard axle ratio is for an 85 K-10, but let's say it's 3.73.  First gear on a 700r is 3.06.  3.06 multiplied by 3.73=11.4138.  Let's divide 3,833 lbs./ft by 11.41= 335lbs./ft.   Ok, we need some help here:

Does the 3,833lbs./ft. rating  mean by itself---in other words anything before entering the rear axle---whatever torque the engine puts out plus the gear ratios in the trans?   OR the engine output + trans ratio + rear axle ratio?

HELPO!


BTW, i really appreciate the work you are doing.  i'm not just saying that either.

[pholliday1]

Some other factors come into play here like tires size and condition of current axle and how often will this be in 4 wheel drive. You can cheat running a bigger tire depending on the size of your right foot on the gas pedal. Confused by" plans to beef up the 7004r with a better clutch" is this a standard? If your heading the direction of a bigger tire and leave your stock gearing in the axles your engine will"SEEM" less powerful because of the tire size to gear ratio difference. There are many charts out there to figure tire size to gear ratio. Give us some more info on your plans and someone here will defiantlty try to get you pointed in the right direction.

[bake74]

     I believe, but could be wrong that the rear would have a 12 bolt and the front has either the 10 bolt or Dana 44.  Either way as mentioned, if you plan on upgrading your 700r4 (you can beef up the 700r4 with internals to make it 2 - 3 times stronger than stock), the axles will become the weak link in the suspension unless you have weak u-joints.
     Also as mentioned, depends on how you plan on using your truck.  If it is going to be a street truck with occasionally fire roads or mild off road, your axles are fine (unless you plan on doing burn out competitions, then they won't last either), if you plan on doing more rugged off roading, you need to be prepared to sometime down the road fixing your broken axles or swapping in 3/4 ton axles (what most people tend to do ).
    If you drive it normally the axles should last a long time.

[klaussk]

Wel lto be honest the only thing i really know about transmission upgrades is that I dont know anything about them haha. My dad said we should put a better clutch in it. And if anyone knows some good ways to make the transmission strong ,please share. the truck will be a Daily driver. Occasionaly it will go off road but I wont be beating it hard. And once in awhile I will have to do a burnout but it wont ever be the long drawn out burnouts you would see in a competition. Is there a way to make the axles I have now stronger for a reasonable price (this hole truck is a budget build).and i have 33x12.50 tires on it and have  no desire to go any larger

[thirsty]

Occasionaly it will go off road but I wont be beating it hard. And once in awhile I will have to do a burnout but it wont ever be the long drawn out burnouts you would see in a competition. Is there a way to make the axles I have now stronger for a reasonable price (this hole truck is a budget build).and i have 33x12.50 tires on it and have  no desire to go any larger

I would run what you have in it for now if it is a budget build. If you break it then fix it with an upgrade. I have broken my share of universals, axles, and differential components. I can honestly say that I never broke any of those unless I was really beating on a truck/jeep. I always deserved it when it happened. For example...My last rear end detonated doing brake stands with a sm465 seeing how long I could hold it in high gear in front of my buddy's race shop. Everybody used to lay down some rubber out there and about once a month I would roast some 33" rubber when the ford guys would brag about the little burn outs they did. I deserved that one for sure. It's beating on it enough just starting the brake stand then add shifting a couple times during it. My point is that I have punished a few 10 bolts in the past and they can take quite a bit but everything has it's breaking point.

[klaussk]

As long as it wont break from simply being to weak for regular use then I am fine with it. I dont plan on beating it to hard. I think I am gonna look into better parts so I know what to get when I do break something. I say I wont beat on it now but it doesnt have a 406 in it right now. That statement about not beating it may prove to be false

[Irish_Alley]

my buddy ran 38's on his blazer with the stock axles

[78 Chevyrado]

From my experience, if it's a high mileage 10 bolt, AT LEAST replace the spider gears.  Thats what trashed the axle and trans in my 87.  it had about 180k miles on it.  one of the spiders failed and trashed the axle and trans completely.  upon inspection the spiders were really worn, like the PO had mismatched rear tires or something.

[bake74]

From my experience, if it's a high mileage 10 bolt, AT LEAST replace the spider gears.  Thats what trashed the axle and trans in my 87.  it had about 180k miles on it.  one of the spiders failed and trashed the axle and trans completely.  upon inspection the spiders were really worn, like the PO had mismatched rear tires or something.

     I agree, even with a budget build, it is always a good idea to at least look everything over so you know what kind of shape it is in.  Then at least you have knowledge of the good and if there is any questionable parts.

[klaussk]

well the truck has 96000 miles on it. and I dont think it was ever ran hard. it definetly did alot of sitting though. I think I will get some better spider gears that are a little stronger. I have a long history of breaking anything and everything on my vehicles. So I dont want to eventualy get this truck to be dang near bullet proof. But after I get the new engine in her I gotta go slow with more parts. The wife is startin to get agitated with the amount I,ve put in to the truck