Couple BA-10/5 questions

Sorry guys but I'm on dial-up here and just can't bring myself to wade through a thousand posts saying "it's junk, throw it away" but not actually offering any useful info. God knows I'll tell anyone who will listen to never buy a jeep with a peugout tranny or a 2.8, but somehow one has wound up in our driveway.:doh: Hey, when you can score a clean, driveable Waggy for under $500 who cares what the transmission is. And it could be worse, my MJ had a god-awful torque-flite in it when we bought that. As long as it keeps working we'll leave it in there, when it dies we'll stuff an AW4 in there and be done with it.

So, anyways the question are:

1) The thing shifts like a tractor, especially when it's cold. And I believe the second gear synchro is pretty much toast. It's got a lot of miles on it and I figure it has at least earned a fliud change. So, what does it take for fluid? Anyone had any particular luck with any sort of additive?

2) What's output shaft spline count/length on these? More specifically will a 21 spline NP242 off an AW4 bolt up? We've been running 242's for too long now to put up with this whole shifting in and out of 4wd depending on road conditions business if we don't have to.

You have a peugeot trans? It takes 10w30 motor oil(you can choose the brand), and yes, i do believe your 242 with 21 spline input will work.

I am with ya on this. Why fix it until it's broke. My MJ has the puke gut trans but it keeps on going. Mine also shifts hard in the cold, takes a few miles to warm up, and the second gear syncho is toast. I picked up another trans and tcase in good working order for $100, way cheaper than any AX15 I have found. I don't wheel this rig or it would be a different story. I have heard of guys in the cold weather running synthetic oil to help the shifting, thats what I am going to do.

Either synthetic GL-4 or GL-5 or engine oil will work for the BA-10, especially in colder climes. The BA-10 uses aluminum synchroniser rings, so the trouble with "yellow metal" that we have in the AX-15 (which requires GL-3) is a non-issue.

Of course, the aluminum doesn't last as long, which is why you're losing sync in 2d...

Bear in mind that the BA-10 was designed for a vehicle with about 2/3 of the weight, half the engine, and maybe 1/3 the power of the XJ/MJ w/242ci, which makes longevity an issue. Start looking for an AX-15 now. I went through four BA-10s in my 88XJ in the space of about four years, and I was trying to not abuse them (primarily on-road, gravel road, and mild terrain. NO crawling, on 31" tyres.)

For your rig with the torque-flite - what engine? If it's got the V6, you have a modified "baby 904" - which is an A904 with a Chevvy metric-patterned bellhousing. The 4-150 will likely have the same pattern.

In this case, switching to an AW4 will be more trouble than you want to get into. A simpler swap would be to get a 1988-up THM700R4/4L60 and transfer case out of an S-series with V6-60 (4WD) or from an S-Series or F-Body (2WD) and swap that in. The THM700R4/4L60 is not electronic (unlike the AW4, which requires control electronics,) and can be readily found with the GM "metric V6" pattern. You'll have to fab up something to mount the crossmember, but that won't be anywhere near as difficult as the wiring headaches you'd let yourself in for with the AW4 - and the AW4 never had a bellhousing to accept the GM Metric V6 pattern (the AMC V8/I6 and various Toyota patterns are all you can get, AFAIK.) This makes the THM700R4 a much simpler swap, mechanically.

Avoid the later 4L60-E - you'll run into the same problem with electronics as the AW4. I don't recall when those rolled out offhand. Also, avoid the 1987 and earlier THM700R4 - they're best used by filling with cement and using a boat anchors...

Thanks for all the replies. 5-90 I especially appreciate the time and effort you put into your reply, that's some excellent info. Unfortuenately most of it is wasted on me. I had been up a very long time when I posted that and perhaps I wasn't as clear as I could have been. We don't actually own 2.8, it's just one of the 2 things I tell people to avoid. The t-flite was a YJ 258 unit that a previous owner had swapped in to replace the original peugout. It thankfully expired within the first few months and we swapped in an AW4 and 242. So what I meant was that we would swap in another AW4 to replace the peugout in the waggy when it dies.

So anyone know for sure if the 242 will bolt up? Might be a good project for next weekend.

The 242 has the same bolt pattern as a 231 which was used with the BA10 trans. The only difference might be input gear length.