300 M rear axles and flanges

[Neil826]

Yeah I would talk to RCV and see what they think. 32 spline is the next upgrade and from what I understand fairly easy. I know RCV has made 32 spline shafts for 80's. Just for reference what size tires and engine are you running?

1fz turbo 400hp, 37” stickies.
Unfortunately being in Aus we don’t exactly have Dana/14 bolts at every junkyard. So kinda trying to run what I’ve got axle wise at the moment.
I’ve also considered as a science experiment throwing stock shafts in a lathe and turning down a taper/ stress relief behind the splines to hopefully prevent failures at the spline in the carrier

 

[Nay]

Actually the went with larger then stock studs and add 4 more. I wish they had gone with the stock size then I would not have had to drill out my hubs .

Curious about this….after reading this most entertaining thread…

I installed RCV fronts six months ago, already have ARP studs there. Rear 300M and ARP studs for the rear have been on the shelf for a year while I’ve debated the extra dowel bit.

Decided I’m going to leave the two dowel setup and stick with stud upgrade only for the RCV.

The bit about larger studs…looks right on the beer cooler…?

Sticking with two dowels I can carry stock spares still and I have an OEM e-locker side machined already like RCV does. Thinking this is the best approach for 38’s and stock leaky motor with 5.29’s.

 

[Broski]

Curious about this….after reading this most entertaining thread…

I installed RCV fronts six months ago, already have ARP studs there. Rear 300M and ARP studs for the rear have been on the shelf for a year while I’ve debated the extra dowel bit.

Decided I’m going to leave the two dowel setup and stick with stud upgrade only for the RCV.

The bit about larger studs…looks right on the beer cooler…?

Sticking with two dowels I can carry stock spares still and I have an OEM e-locker side machined already like RCV does. Thinking this is the best approach for 38’s and stock leaky motor with 5.29’s.View attachment 3645919
View attachment 3645920

Please clarify
I’m not understanding.

I just have a spare hub now to go with my stock shaft's

 

[baldilocks]

Curious about this….after reading this most entertaining thread…

I installed RCV fronts six months ago, already have ARP studs there. Rear 300M and ARP studs for the rear have been on the shelf for a year while I’ve debated the extra dowel bit.

Decided I’m going to leave the two dowel setup and stick with stud upgrade only for the RCV.

The bit about larger studs…looks right on the beer cooler…?

Sticking with two dowels I can carry stock spares still and I have an OEM e-locker side machined already like RCV does. Thinking this is the best approach for 38’s and stock leaky motor with 5.29’s.View attachment 3645919
View attachment 3645920

Larger studs?

 

[Nay]

Larger studs?

Yes curious on the comment that RCV required larger studs, meaning mandatory drilling of the hubs.

 

[Nay]

Please clarify
I’m not understanding.

I just have a spare hub now to go with my stock shaft's

I read in your comment that the RCV flange uses larger studs and so choice of dowel number notwithstanding, you had to drill your hubs. Did I read that right?

 

[baldilocks]

Yes curious on the comment that RCV required larger studs, meaning mandatory drilling of the hubs.

The studs remain the same as stock. The drilling has to do with the dowels. I drilled all six on one side and only four on the other side leaving the two factory studs in place. I figure that the studs only come into the picture when and if the studs become loose. In other words, insurance. I do have extra hubs and RCV flanges. Remember that carrying an extra RCV flange covers you.

 

[Broski]

I read in your comment that the RCV flange uses larger studs and so choice of dowel number notwithstanding, you had to drill your hubs. Did I read that right?

Like Steve said only the dowels need to be drilled larger.

Did you drill for larger hardware?

 

[Nay]

The studs remain the same as stock. The drilling has to do with the dowels. I drilled all six on one side and only four on the other side leaving the two factory studs in place. I figure that the studs only come into the picture when and if the studs become loose. In other words, insurance. I do have extra hubs and RCV flanges. Remember that carrying an extra RCV flange covers you.

The flange covers you if that’s what fails, right? I guess this comes down to assumptions on what might fail - the spare hub is the safest bet since stud failure isn’t necessarily trail reparable, but if you leave the dowels at 2 then stock axle bolts right back up if you don’t blow up the outer hub. This assumes the RCV axle shaft could be the failure point.

What we can’t know is what happens if you don’t have perfect dowel drilling and that unbalances the shear load. Take any component like this out of a perfect circle and what does it eat?

Some of this is lazy conservatism on my part, but really what I’m solving for is upgraded strength in the OEM design configuration and not having to cut an axle shaft out of the e-locker.

That’s also why I keep resisting temptation to upgrade power…

 

[Nay]

Like Steve said only the dowels need to be drilled larger.

Did you drill for larger hardware?

No it was just a misread of your post in studs vs dowels. I decided on stud upgrade and no extra dowels to keep a theoretical balance that a) if a RCV shaft or flange fails the stock bolts right up and b) better in the extreme to lose the hub studs than a diff internal.

As you noted, a spare hub and OEM shafts solve for both a) and b) on the trail.

 

[baldilocks]

The flange covers you if that’s what fails, right? I guess this comes down to assumptions on what might fail - the spare hub is the safest bet since stud failure isn’t necessarily trail reparable, but if you leave the dowels at 2 then stock axle bolts right back up if you don’t blow up the outer hub. This assumes the RCV axle shaft could be the failure point.

What we can’t know is what happens if you don’t have perfect dowel drilling and that unbalances the shear load. Take any component like this out of a perfect circle and what does it eat?

Some of this is lazy conservatism on my part, but really what I’m solving for is upgraded strength in the OEM design configuration and not having to cut an axle shaft out of the e-locker.

That’s also why I keep resisting temptation to upgrade power…

Perfect circle? Deflated 37’s form anything but a circle. Right foot and confidence determines who smiles. . Suck’m up tight and do what you do.

 

[Nay]

Perfect circle? Deflated 37’s form anything but a circle. Right foot and confidence determines who smiles. . Suck’m up tight and do what you do.

Haha. Perfect circle of a splined shaft running inside a spindle. How much does that have to be off before the splines chew up the spindle? I hate hammering out cone washers as much as anybody, but isn’t the design premise to leverage a tapered hole to ensure it doesn’t run off center?

Seems analogous to arguing hub centric wheels are superior to lug centric especially running big tires under load. Those OEM hub centric lug nuts aren’t tapered because they aren’t centering the wheel - go lug centric and they are tapered because you would never get a good enough center otherwise and then your lugs are sheering off at 75 mph.

I dunno - bugs me that you have logically have to be extremely accurate to avoid a wear based failure. It’s a lot of money to be concerned that it doesn’t actually work.

 

[Broski]

Would have been nice if RCV would have lift the dowels the same size as OEM.
Now if you don't drill for the new size in your hub you won't have any dowels working for you as the holes in the RCV flange are bigger then the OEM dowels.

 

[Nay]

Would have been nice if RCV would have lift the dowels the same size as OEM.
Now if you don't drill for the new size in your hub you won't have any dowels working for you as the holes in the RCV flange are bigger then the OEM dowels.

Ok this is what I initially misread in your post I quoted above that hadn’t made sense to me - it’s not the studs you were talking about it’s the dowels, and of course you don’t reuse the two OEM ones if the RCV are larger. That nagging thing that kept me talking about this.

Maybe I’ll just ARP upgrade the studs, install the OEM shaft with the e-locker splines machined off that I’ve carried as a spare for a decade, and revisit this if I start breaking more stuff. That would also let me totally not rebuild the rear hubs and I can have my spare steering box rebuilt by Redhead and ported for hydro assist with these Franklins.

Of course if I do this now I’ll break it.

 

[Broski]

I went ahead to the larger dowels and the ARP hardware. Zero issues with this setup.

If you all ready have the RCVs I say drill away and run them.

I have read about quite a few issues with Redhead steering boxes lately.

You could always send the box to @Outsane for a rebuild and tap thats what I was planning to do with my spare box and 105 upgrade kit.

 

[Nay]

I went ahead to the larger dowels and the ARP hardware. Zero issues with this setup.

If you all ready have the RCVs I say drill away and run them.

I have read about quite a few issues with Redhead steering boxes lately.

You could always send the box to @Outsane for a rebuild and tap thats what I was planning to do with my spare box and 105 upgrade kit.

Yea, I’ll do it. Probably take the hubs up to Slee if they drill since they are right by White Ranch which is a fav mountain biking area. Then can go to New Terrain brewing and have beer. I am forgetting that I had a good plan, and all the hub rebuild stuff is sitting in the box o projects. OEM shafts then need that spare hub for backup (or maybe we should drill them, too). I started down this road when one of my sons decided to long travel and then upon proving that to break, one-ton his ‘04 Sequoia so we can run some of the harder stuff out in Montrose and Grand Junction now that I spend a lot of my time close by in Gunnison. Probably outta stick with the plan even though he’ll never finish that project .

Appreciate the info on Redhead, I guess we went down this road with West Texas Off-road and steering boxes, I have the 105 upgrade as well. Will reach out to @Outsane.

 

[SNLC]

Only probs we have had with Redhead is they were not using the OEM seal/washer and nut on the box adjuster. They we using an upside down nylock nut! That leaked on me bad and all boxes since I requested they use only OEM parts.

I haven’t had them do a box though in going on two years. We did pull one of their boxes because the customer wanted a new 105 box. He reported back that the new box was better, ie feels better driving.

Cheers

 

[Nay]

Only probs we have had with Redhead is they were not using the OEM seal/washer and nut on the box adjuster. They we using an upside down nylock nut! That leaked on me bad and all boxes since I requested they use only OEM parts.

I haven’t had them do a box though in going on two years. We did pull one of their boxes because the customer wanted a new 105 box. He reported back that the new box was better, ie feels better driving.

Cheers

Thanks for the thoughts here, that helps. I’ve considered a 105 box because “rebuild” really isn’t, right? It’s a seal, etc. refresh. There was a time when a 105 box out of the UAE was $1,500. My spare had 140K miles when pulled so it’s half the mileage of what’s on the truck and that half has all been 37” or bigger tires.

I’ll put out a different thread if wanting to talk through it more so we don’t steering box redirect this one .

 

[Broski]

Only probs we have had with Redhead is they were not using the OEM seal/washer and nut on the box adjuster. They we using an upside down nylock nut! That leaked on me bad

Will that seem like a problem to me. Things like that should not happen.

 

[SNLC]

Will that seem like a problem to me. Things like that should not happen.

I was just happy the leaky box was on my 80 and not a customers Cruiser.

Cheers