Why not go with developing 32 spline custom shafts instead of 30 spline? Just curious.
300 M rear axles and flanges (2 Viewers)
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I'm sure RCV would entertain it... reality is FF shafts generally break at the side gear which is stuck at 30 unless you do some 100/200 reverse trickery which is doable using side gears from a 100 e-locker or ARB or a complete 100/200 diff. We used to do 4.88's in 100's using an 80 carrier and 100 side gears, this before Nitro came out with 100/200R specific gears.
Early 30 spline FF shafts are ~35mm at the seal surface, 36mm for the later shafts. This might have an impact on how much shaft will fit thru the spindle without boring.
Not sure what you mean. Early full float shafts? I didn't know their was a early and late 30 spline full float shaft.
Absolutely... really the 90-97 is a later but still 35mm, 30 spline FF's started in MY 1976. Buy a 42312-60090 rear FF and it supercedes to 42312-60091 which was used in a 2000 era non-US 8x with the 36mm seal, same as the 98+ 105/7x stuff was getting too. They are visibly different seals as 1mm makes a big difference when dealing with an already incredibly thin seal. Likewise buy a new OEM Toyota rear FF for an 8x and you're likely getting a 36mm seal surface... not much room left through the spindle BUT we know the shaft can be at least 36mm whereas the 30 spline shaft is 1.31" (going by memory there) which is ~33.3mm. EDIT: confirmed 33mm/1.31" OD on the 30 spline
EDIT: the 32 spline shafts are 34.8mm OD (shaft, not seal surface), they use the 36mm ID seal so not a huge "step-up" for the seal surface. Assuming the spindle ID on an 8x would accommodate the 34.8mm shaft OD, it's totally doable with an ARB or E-locker and likely an open diff too.
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ChaseTruck
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I keep reading this, sort-of from the cheap seats, and the suspense of waiting until someone puts a 14-bolt back there to deal with those pesky 40-inch tires is just becoming too much. Off to read the floor mat thread....
HDJdreams
SILVER Star
The biggest reason to run 32 spline shafts is to run the newer style 9.5 gears with a significantly wider tooth face and thicker pinion shaft.
IF you are doing lockers and gears anyway and planning on HD shafts like these, using the newer gearset will give more strength for about same price. The same gears that Toyota uses behind 450 ft-lb twin turbo V8 diesel in heavy 200 series. (Those of you running V8s on 40s may want to go this route.)
If you already have gears and lockers, the these 300M 30 splines are the way to go!
IF you are doing lockers and gears anyway and planning on HD shafts like these, using the newer gearset will give more strength for about same price. The same gears that Toyota uses behind 450 ft-lb twin turbo V8 diesel in heavy 200 series. (Those of you running V8s on 40s may want to go this route.)
If you already have gears and lockers, the these 300M 30 splines are the way to go!
When I broke a Nitro rear shaft in Moab two years ago they told me the warranty had no horsepower or tire size limit. The stories sound different. Your rig is heavy and you wheel a lot so I’m still of the mind that you might as well go with tons or custom built axle assemblies.
How strong of a shaft can the hub studs stand up too? I don’t agree with the super long splines on the nitros but they did for you what they were supposed to so.
Those who push their equipment hard and often need to do regular inspections of everything. You have reminded me to take a look at my nitros, it’s been a while.
And the 100/200 diff is a direct swap into the 8x outside of the side gear splines. Gears/install kits are significantly more $$$ for the 100/200 (gears & install kits are double fwiw) but in the grand scheme of an entire build.... were talking a few hundred dollars.
RCV is going to want some quantity of committment to proceed or cost of a single set would be likely double as well. Mark Williams Axles could do a 4340 shaft with gun-drilling, etc with the 32 splines on either end.
This was my point two years ago when I broke one that was actually defective. I found out these shafts are made in Korea but supposedly “assembled in USA”. I got hate posts because I blamed lack of QC oversight in a factory on the other side of the planet.
On the other hand, these one piece Nitro shafts cost under $500 or at least they did last I knew. So, maybe the old adage, “you get what you pay for” has some applicability here.
The saving grace is that our rear is a full floater so a broken shaft won’t necessarily end the day.
So if the 32 spline is 34.8mm then the spline tooth size they are using are probably the same between the 30 spline and 32 spline. Thus the bigger diamater of the 32 spline which is the case with most other axle shafts. According to the axle charts Ive looked at, if both axles are made from the same material, going from 30 spline to 32 spline would give about a 20 to 25% increase in strength. So if the stock 80 30 spline of oem material fails at lets guess an estimate 8,000 ftlbs of torque, the 32 spline should hold up to 9600ftlbs or more. Going to chromoly or 300m would increase even more. I know a few guys on pirate have gone 35 spline shafts with ARB lockers being used. Not sure if they machine the spindle.
The OD of the RAX inner axle seal is 41mm so there is still a good deal of material there available if one did have to open it up a bit for a larger OD shaft. Could be a really neat option. What fails next?
The OD of the RAX inner axle seal is 41mm so there is still a good deal of material there available if one did have to open it up a bit for a larger OD shaft. Could be a really neat option. What fails next?
Or retro fit a 100 series third (stronger R&P), OEM 32 splined axles and custom hubs to suit the 32 splined axle flange bolt hole PCD and hardware
Or 100series 3rd, custom 32 spline axles, custom 32spline hub flange
Which one is least spendy?
105 / 79 series REAR runs heavy R&P, 32spline a FF axles, larger diameter hubs with larger bolt PCD, 8mm dowels and 10mm hardware.
105 series FRONT runs same 3rd, same R&P, same axles, same birf, but hubs are beefed up to match the rear
HDJdreams
SILVER Star
It’s my understanding that the “newer” (98+) 9.5” gears and 32 spline differential will fit in 80 series and old 3rd member. So no 100 series 3rd needed, just the “guts”.
You may be right. I think carrier bearings were beefed up too, but not certain
ARB 152 fits normal Land Cruiser "9.5" third member...
Also Nitro already makes shafts it seems...
I am not sure but it seems like 200s are semi float only...
Also Nitro already makes shafts it seems...
Nitro Pro Series Chromoly 32 spline Upgrade Axle Kit
Nitro Pro Series Chromoly 32 spline Upgrade Axle Kit
www.justdifferentials.com
I am not sure but it seems like 200s are semi float only...
Options are a plenty!
Correct, that is exactly why we are discussing that as an option.
ARB 152 fits normal Land Cruiser "9.5" third member...
Also Nitro already makes shafts it seems...
Nitro Pro Series Chromoly 32 spline Upgrade Axle Kit
Nitro Pro Series Chromoly 32 spline Upgrade Axle Kitwww.justdifferentials.com
I am not sure but it seems like 200s are semi float only...
Wild. I wonder how new that is?
The 32 spline on the diff side is easily solved one of several ways including a full diff swap and/or just mixing/matching carrier parts... all been done on that side.
The idea of using the 32 spline diff, shafts and a larger 100/105 hub side pattern and larger studs with the 80's 6x5.5" pattern is a neat idea
The idea of using the 32 spline diff, shafts and a larger 100/105 hub side pattern and larger studs with the 80 6x5.5" hub is a near idea
105 hubs are quite a bit beefier.
Bolt PCD for axle flange studs went from something like 94mm PCD to 106mm. Not certain of measurements, is a long time since I measured all this.
One thing that might be a fly in the ointment is the amount of material left on an 80series hub.
If a blank 80series hub was available to machine to suit 105series flange and hardware, there may not be enough meat at the outer diameter to capture the hardware due to greater diameter PCD and thicker hardware
Wheel centre hole is larger on 105 rims to cope with the bigger hubs
Someone needs to do some measuring
Curious though does the 105 hub use a different spindle and hub bearing, or is it just a different wheel hub on the same old stuff?
Most full floating axles (typically) mirror the carrier bearing size for the inner hub bearing, if the carrier still fits the 9.5 third...
Most full floating axles (typically) mirror the carrier bearing size for the inner hub bearing, if the carrier still fits the 9.5 third...
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