The new F150s and Mustangs use what is called a "Super 8.8". It has a bigger ring and pinion as well as more axle splines and a different housing. I'm curious to see if this becomes a popular aftermarket axle
Anyone running a Ford 9" front and rear?
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OP
My main goals are:
- Keep the weight down (This is a big one for me)
- Improve ground clearance
- Stand up to 37" to 38" (Absolute Maximum) tires
- Stand up to a Golen Stroker (Sitting in a crate in the garage)
- Provide reliability, without constant maintenance
I'm not a heavy foot type and am more of a slow calculated crawler. I push the Jeep, but realize it's not a buggy.
Have you broken anything yet? The stock 9 inch they run isn't a huge upgrade depending on if they got lucky with an N casting. Just saying that the 9 inch is a rabbit hole. You can get to 40 spline drilled shafts if you want (or think you need) them. On the other hand, if you think their setup is an upgrade there is no reason not to try. Assuming you can weld.
OP
This is part of my problem now. If I wanted to run 5.13 I could. However, 5.13 wouldn't work with 37s and a 42RLE. The next step up is either 5.29 or 5.43.
A smart right foot makes things last. You can break any axle with enough skinny pedal in the wrong situation.
B00mb00m
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I would do the opposite hah, run a F9 front and leave my jk44 rear (35 soline) alone. So your buddies are running the 5.13/5.14? Wonder if that is so close they are basically not scrubbing? I'm thinking for like driving 50mph on snow.
OP
I'm starting to sense what you said, it's a rabbit hole. In terms of breakage, a few u Joints and a busted ring and pinion. Ever since the R&P issue, I'm much more cautious about going into places I probably could go, but don't. I have confidence in the current 44 setup, but know where the limits are. 60s would be ideal, but I'm going through all the options before making a decision. Based on discussions with Currie and Dynatrak, it also seems like their 44s would work in my case. Decision, decisions!
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I do run 5.13 with 37s. It's actually slightly better than 35 with 5.13 only because I have a lot of local roads at 55 and now third gear lets me drive those at 3k rpm and OD only comes on on the interstate (65mph)
OP
Or a hp 44. Although it doesn't really matter at this point. Cost will be about the same.
OP
OP
If you go true hi9 you add about $1500+. The guys at ruff stuff are solid as are their products. Just another option for 9 inch housings.
Well, the cool thing about running a Tru Hi9 front with a HP 60 rear is being able to tell your buddies that every time you change the gear oil it takes a case or 12 quarts. That also means you will use more gear oil in the first 1000 miles, 24 quarts, than most Jeep owners use in the life of their rig.
From TruHi9 website “We have 4.11, 4.57, 4.86, 5.14, 5.38 gears in stock.”
You know in case need more to think about
Hold that thought. I'm trying to see how far I can pee. Seriously though, what do you consider an axle with a decent safety margin for taking, say my kids, in to the back country and not wanting to make on trail repairs regularly with a slightly hot 4.0? Against 35's and again against 37's. What's your real world experience?
I'm not the one to ask since my view of 37's is far more realistic than most based on the experiences of running them, and building a few axles to run them. Give me a good reason to run 37's that isn't based on aesthetics and we'll talk.
Ok, how about 35's and a hot 4.0? Hp Dana 30's aren't as disposable as they used to be. Is it still worth building a 30? Option 2.0 is an old hp or jk 44 built with Chevy/ford outers and locking hubs. I like hubs.
Some are 8.8, mainly Currie, IIRC, some are 9inch, and some are 10 inch. I am currently building a 10 inch high pinion 9 from GearWorks and Spidertrax. Waiting on Spidertrax housings to come off backorder status. https://bomberfab.com/collections/d...-drop-out-5-43-billet-35-spline-billet-locker
The GearWorks cases can be built with 3.2 cases, 3.8 inch cases, or a huge 4 inch case.(think trophy truck) The 3.2, 3.8, and 4 inch cases utilize load bolts to fight ring gear deflection. This solves a lot of issues that you eluded to. I still haven't decided if I will go 35 spline or 40 spline
On another note, Currie 60’s are built with load bolts as well.
My personal Gearworks HP 10 inch third member. It is massive. I will unbox the rest of the parts next month and start putting it all together.
Most of the Ultra4 rock racing rigs are running GearWorks stuff with Spidertrax housings. Lovell from KOH:
Currie builds some really nice stuff too. Although I am not sure they support HP 9 inch stuff anymore, although I could be wrong, as I am pretty much sold on the Gearworks thirds and gears.
The 9 inch/fabricated 9 inch is popular bc of the mass amount of gear choices, its easy to swap out thirds, it uses a pinion support with an extra bearing and has been proven in drag racing for years and years. The 10 inch gears are very close if not stronger than a 60 9.7 inch gear. The tooth contact is another strong point. They can be run with up to 40 spline axles and everything in between. Lightweight as well. Some of the housing offerings from SpiderTrax use heat treated chromoly 4340 axle tubes for incredible strength gains.
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There are vast amounts of 5.13’s and 5.38’s these days for the Ford 9/Fab 9
yukon, sierra, us gear, etc all make 5.13’s.
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