1981 Pick-up Build

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Got the diffs back from the shop and some rebuild parts for the front axle. Classic City Offroad did me right and only charged me for a new seal housing and no labor for the busted diff. These guys have always been great if anyone needs work done in the Athens area.

Finally locked f and r!

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Selectable in the front and Spartan in the rear. Couldn't stomach 30-spline axles right now, so I'll be keeping my fingers crossed with the stock birfs.

Also, trussed up and installed new seals, bearings, degree shims, etc in my other front axle for the swap. Hopefully this will get rid of that bad camber I had with the old axle.
 
There's my 14MM wrench, I've been looking everywhere for that thing.:moon:

You've been a very busy boy, looking very nice!!
 
It's actually a 13mm. :flipoff2: At some point somebody lost the OEM nuts and replaced them with those stupid off size aftermarket nuts.
 
Yah know, If I'm not mistaken ARP replacement studs are 13 MM so ya might have something there.
 
tgreco said:
Couldn't stomach 30-spline axles right now, so I'll be keeping my fingers crossed with the stock birfs.
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I had the same thought when i locked the front. broke the outer on the short side on the first ride :(. If you can swing it, get the 27 spline longs outers and you should be good for a long time. Unless you're running 40s and drive like Ted
 
radioridge said:
I had the same thought when i locked the front. broke the outer on the short side on the first ride :(. If you can swing it, get the 27 spline longs outers and you should be good for a long time. Unless you're running 40s and drive like Ted
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What size tires are/were you running? It seems like their are conflicting thoughts on the 27spline longs. I'm all about going that route if it would be money well spent. I need to make my mind up before I put this axle back together.
 
tgreco said:
What size tires are/were you running? It seems like their are conflicting thoughts on the 27spline longs. I'm all about going that route if it would be money well spent. I need to make my mind up before I put this axle back together.
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not likely to get a black and white answer here, there are too many variables. Driving style, rig weight, tire size, type of wheeling, etc... are all things to take into consideration.

Heres the way i break it down:
  • Factory Birf: not question of IF but only WHEN you're gonna break one, probably many. It's only a matter of time before you pony up.
  • 27 Spline: You'll probably break one sooner or later but more likely later running 35s and a selectable locker up front, just all depends on factors above but a very acceptable compromise.
  • 30 Spline: They do break but primarily only in extreme/hardcore conditions. You're likely not there yet but the question has to be asked: will you be and if so when? Also, the 27 can be carried as a spare so it's not entirely money lost when you ultimately go 30 spline, and you will.
 
Thanks Ted - this was kind of the impression I was under.

I'm starting to lean toward picking up some chromo 27-spline birfs as TG has them on sale. In regard to the 27-spline stuff, is upgrading to the chromo inner axle shafts worth the extra $90? Does going with the chromo inner axle shafts move the weak link to somewhere else that I don't want it (i.e. hub, r&p, etc)?

Edit:

Remembered this thread: Bobby Longs Axle Breaking Machine Results - Pirate4x4.Com : 4x4 and Off-Road Forum

With these results (this thread is circa 2006, so things are probably somewhat different now):

Axle breaking torque table.webp


So: with 27-spline birfs only, my weak spot theoretically moves to the stock inner shaft. With chromo inner shafts, I'll move my weak link to the hub (which I think would be an easier fix). This assumes that the new TG birfs are equivalent in strength to the original Longfields.

Conclusion: get the chromo 27-spline birfs and inner axles, unless someone tells me that blowing up the hub leads to more expensive damage that I am not considering.
 
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that's good info and looks like my next upgrade will be a 4340 T-Case output shaft. I'm kinda in the same boat as you , just in a different area of the rig.

Not a bad plan at all but you might get away with stock inners, I don't believe they take as much abuse as the birfields seem to.

Raw data is one thing but real world application is another. Again just one guy's opinion but given the size and weight of your truck I'd save the $90 and put it toward the (ultimate) 30 spline savings account. If you follow the progression many of us have (and you seem to be) you'll be eyeballing 37s+ sooner than you think and the 27s will have to go.
 
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The primary problem is with the bell. That is almost always the failure point of any birf (stock, 27 sp, 30 sp, etc). I'd say from a purely budget standpoint, is buy the 27 sp birfs and put them in and go. Keep the stockers as spares. I agree with Ted, your already on the road to RCVs so may as well save the pennies up so if you break an inner you can just jump in on the 30s and roll on.

I haven't seen you wheel and don't know what your final gearing is, but you might get by with one 27sp to have as a spare and Sun's til they blow and go 30sp. Generally, low gears + weird angles + happy peddle = new parts.
 
jynx said:
I haven't seen you wheel and don't know what your final gearing is, but you might get by with one 27sp to have as a spare and Sun's til they blow and go 30sp. Generally, low gears + weird angles + happy peddle = new parts.
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Oh it's a sight to be seen :hillbilly:. Historically, I've relied on the skinny pedal due to open diffs. I hope that is about to change. I'm running a single 4.7 tcase and 4.88 gears. I like the ideas above and may just pick up some 27 spline birfs. The Marfields have a slightly better warranty than the TGs (2yr v 1yr), but if and when I break, it'd probably be time to go 30 spline anyway.

I appreciate everybody's input and patience while I wade through the same questions that face most Toyota owners.
 
tgreco said:
Oh it's a sight to be seen :hillbilly:. Historically, I've relied on the skinny pedal due to open diffs. I hope that is about to change. I'm running a single 4.7 tcase and 4.88 gears. I like the ideas above and may just pick up some 27 spline birfs. The Marfields have a slightly better warranty than the TGs (2yr v 1yr), but if and when I break, it'd probably be time to go 30 spline anyway.

I appreciate everybody's input and patience while I wade through the same questions that face most Toyota owners.
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So that give you a crawl ratio of 89.5:1 just FYI. Marlin for the win, that is assuming they have it stock. Now, it;s time to start looking at beadlocks so you can dem tars down to 5 psi. :steer::steer:
 
Finally got the axles and knuckles back on. Still got a few things to do, but it's going to be a push to make it to Chocco this weekend.

Those inner axle c-clips gave me some trouble when reinstalling the birfs. The zip tie trick ultimately worked, but for me I used the smallest zip tie I had as the thicker ones pushed off before the birf splines could slide over the ring.

And for my tech tip of the day, make sure to look at the lbs. side of the pull scale and not the kg side when setting preload. It'll make your day a lot better. :bang:

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And don't mind the mess...

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Looks good Tony. It did really well this weekend. Btw, I found your water bottle in the parking lot Saturday morning. It's in my tow rig, I'll give it back next time we wheel together.
 
CID 96 said:
Looks good Tony. It did really well this weekend. Btw, I found your water bottle in the parking lot Saturday morning. It's in my tow rig, I'll give it back next time we wheel together.
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Thanks Cid, we woke up a little late and rushed to get out of camp. Wish I could have stayed on Saturday, it looks like you guys hit some good trails.
 
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