Sounds like your priorities are a little outta whack. 33s w ba10 and stock axles wouldn't last long if PARKED lol.
No offense, but before spending bunches of cash make sure you need it and it's good bang for your buck.
I feel the stock axles arent worth the money to regear unless you know how to do it yourself and save a wad on labor. (about 1100 cheaper for both)
Determine what you want the jeep to be able to do and build in that direction.
For now, i would lift it 2" springs, 1" shackle w shackle reversal, lock-right the d35, and get some knobby 30x9.50 km2. Mayyybe 31 but it will be a dog.
Other good option is 4cyl axles, lunchbox locker rear, 4" spring 1" shackle 33x10.50 km2.
Tried and true formula.
You dont have a v8 so youll be fine w light wheeling for a bit but load ppl into it or go bigger tires, or wheel the ba10 hard at all and its not if but when because the ba10 absolutely will fail.
The nice thing is because of the low mileage you truly have the widest array of options.
But keep in mind, anybody can open a catalog and order crap for their jeep... Build it how you like it, not how every other jeep is built.
Oh no, never would consider the 33's with 3.07. I guess I was saying with just a ring/pinion would something like 3.55 or 3.73 be ok instead of going 4.1 to to 4.56. And yes, I have considered running something like 30-31 for now. I'm in no hurry.
Well you know from experience things quickly escalate and where do you really draw the line?
The stock axles arent usually worth regearing because as you go up in ratio the strength and longetivity of the assembly becomes compromised due to increased loads.
So if you start looking into beefed up axles it snowballs from there... Just for some bigger tires, talker gears and the added strength to use them together.
Ultimately depends how hardcore you plan to go down the road. Baby steps / incrementalism is more expensive... But probably the better option.
Cheapest way out for the best performance without building a Rambo D35: 4cyl axles, all new everything (brakes/seals/rod ends/ujoints/ball joints/etc) and a rear Richmond lock right locker. No setup required it replaces just the spider gears. Streetable if you know how to handle an automatic locker but noisy and clunky enough to scare everybody who rides shotgun.
Locker(s), mud terrains and 4.10s will go a verrery long way to making this thing a great wheeler. And a winch. (i prefer hydraulic but they get pricey. More reliabe.)
What kind of wheeling will she see? Streetable-sensible-holds-its-own? Cuz youre talkin comfort and literally flexibility. Can do! So many unique paths to take with Jeeps, more than one way to skin a cat.
Bought me a set of 2014 stock jk takeoffs. Not my fav choice but WAY better then the stockers. Already got the adapters coming, along with my 1" body lift, and some greasable boomerang shackles that supposedly give another 3/4" lift. Hope this is enough for now.
I don't recall a late model YJ using 21sp - the only exception i could imagine is a 4cyl/5spd.
Can you get a picture of the red and silver ID tag on the tcase in question? That will tell you more about it. Also any more information the seller has that you could provide would help.
Not all of the same spline counts work on each other- that is to say, a transmission with a flush to tail output shaft use a long input gear on the tcase and the trans with the approximately 1/2" stick out uses a short input gear tcase.
Trans side (manual trans) = flush or about .5" half an inch. Its actually like .46 or something.
Tcase side uses short, mid and long length input gears in 21 or 23 spline.
Short = 1.2" (example late yj or mid-90s xj ax15)
Mid = 1.7" (90s yj automatic trans - possibly 4cyl)
Long = 2.1" (pretty sure this is more like what youll find behind the ba10 or an ax5 and probably more likely a 21sp -- however i am NOT 100% certain at this moment (just woke up) and after finding out more information i can help or you can call Advance Adapters and ask for one of their YJ experts. They're incredible at AA.)
Somewhere around 1992 tcase manufacturer New Progess Gear changed internals. Gear tooth angles and a couple other details were changed and early/late parts don't all interchange- i mention this because you'll probably be asked when you order an SYE what its going in so they give you the right one.
Changing an input gear down the road is more expensive in my opinion, unless you acquire a small pile of various yj/tj tcases and mix/match accordingly.
Given that it's almost free leads me to believe they're trying to get rid of it and maybe its not what it seems. Find out what it came out of and report back.
Find out more information or get me pics of the tcase input gear and the red/silver tag and ill go measure my old tcase to double check but this might not be what you need.
They other thing is... When i did my ax15 swap i found a "junkyard" tcase for $40 at a guys house when i was there buying axle parts to eliminate my front vacuum disconnect.
I dumped the water out and old ATF out, poured in wd40 and shook it around, dumped, refilled with wd40, shook around and let it sit for a day, moved it around, let it sit a day and dumped it. Whatever little bit of water was left would cook out when driving. I also used a neighbor's specialty camera scope thing to go in the fill port and check for rust or broken **** inside without having to split and reseal the case.
You have an excellent candidate for an ax15/231 joint swap and to sell your ba10 to someone who needs it that was recently informed by their local transmission shop theirs can't be rebuilt.
Can you reask your speedo question i got confused- what do you want to do?
I think changing splines down the road might bite you - not sure the SYE will be compatible.
If i recall all the YJ 231s have speedo gear provisions and fuel injected models used a mechanism that dropped in on the speedo gear and transferred through a tone ring VSS. TJs and newer i believe did away with the speedo gear provision on the output shaft and use an integrated tone ring.
If youre asking what I think youre asking, and provided im not spewing bs here, you should be ok on the speedo issue.
Ultimately there's an option to run a mechanical speedo pass- thru VSS that can run a FI ECU and mech gauge.
Yes, it's from a 4cyl. I prob should have mentioned I'm picking up the 4.1 axles (in good shape) for $300. Came from a wrecked 95 YJ.
From what research I've done my 207 speedo cable works in the 231 and the mechanical gear may be a direct replacement. But I couldn't find any "for sure." But my thought was I could build this 231 for an AX15 (it's $50).
And thanks Robert. I've really enjoyed it. I td my GF when I was 15 my dad passed on the last YJ at the local dealership. I still remember how upset I was, not mad cause we really couldn't afford it. But I remember it like the lump in a kids throat when they really want something. I told GF I finally satisfied that 15 yo. Lol
The BA10 had both 21 and 23 spline. I don't know if I mentioned that already. 93/94 isn't the absolute definite switchover date for the internal differences. There have been examples of 92/93 with 94+ internals. YMMV.
The input gear is your hurdle. For $50 you can get this tcase and have it for spare parts. Otherwise this might not be what you need. The input gear is over $120 to change out just the one part for AX15 compatibility. So ultimately a junkyard refreshed 231J from a 6cyl YJ is cheaper. I'd pass on this one.
The 207 you have in there now has 12k miles on it, I'm pretty sure it's internally fine.
When you need another tcase is when you go AX15 -- if you find someone who wants to buy your BA10/207 as-is with super low miles you can use that money to fund your upgrade/swap - maybe they want to keep theirs original and you don't. One man's junk is another man's treasure has never been more accurate than when applied to the Jeep YJ.
For now I guess rock whatcha got?
Hard to say.
Personally I have what you probably need -- an AX15 from a 92 YJ. It's 23 spline but it's internal slave and needs a rebuild.
I prefer external slave... but the one in my YJ needs a rebuild, it grinds 1 2 3 4 and Reverse. lol 5th is on it's way I bet.... I'll probably rebuild it myself but the $500 in parts is one hurdle, the space in my cave to tear it apart and fix it is another... my father and I have entirely too much **** in the cellar because we're restoring a 1970 AMC Javelin.
I hate to be that guy, but I gotta agree with the folks earlier that said don't mod this. You have a survivor that will never be original again, while we're not talking some vintage car - just an '87 YJ - it still will only be original once. Why start with this one just to mod it? Its originality makes it original already - any jeep guy is gonna notice how clean an example that thing is and appreciate it.