Drained the tranny - BA 10

I haven't gotten around to draining the BA-10 5 speed trans on the MJ, until today. I drove it around town for a bit beforehand just to make sure it was warm.

The stuff that came out was kind of a funky chunky thinnish gelatinous goop (not metal chunks, no metal on the magnet when I swirled it around in the goo).
I didn't expect super clean oil because the PO did not maintain this Jeep like I would. My question for today is:

What can I run through it to clean the inside of the trans?? Regular oil? Kerosene? I just would like to get all the crap out of there. Anybody ever done this??

...or should I just fill it up and call it good? The BA10 is staying in the truck until I can get the AW4 I have up to snuff for the swap.

Grabbed this off Yahoo Answers:

"BA-10/5 5-Speed Manual Transmission: Use 75W-90 GL-5 Gear Oil. There are 3 plugs in the tranny. One at the bottom in the rear housing - it's a drain - as always open the fill before draining, just so you can get stuff back in!

Another on the passenger's side above the tranny crossmember - this is the "Fill" and "check" hole.

Yet another on the passenger's side further forward in the main body of the tranny, this is a location for the 5th gear switch (not used by the Renix system) - filling or checking from this hole can leave your tranny almost 1-quart below full -- a VERY common mode of failyure/wear for the Ba10/5 is to have serviced the 5-sp from this switch hole - a medium-duty tranny like the BA10/5 really needs to be well lubricated to perform as designed and low-filling isn't the best way to get these things happy."

I plan on filling it from the side hole. Would running some cheap-o regular old detergent-rich oil around the block a few times "wash" it out??

Getting the plugs out was a piece of cake. I ground down a "made in Taiwan" extension to the required size, it now has a special place in my toolbox (works on the engine block drain plug too!!).

Inexpensive gear oil or better yet, ATF would work good for a rinse oil.

I would suggest Redline 75W90 NS for your final fill. I've had great luck with this in keeping my BA10/5s alive under moderate abuse.

I think I ground down a large impact torx bit that had been stripped to make my plug wrench.

ParadiseXJ said:

I plan on filling it from the side hole. Would running some cheap-o regular old detergent-rich oil around the block a few times "wash" it out??

Getting the plugs out was a piece of cake. I ground down a "made in Taiwan" extension to the required size, it now has a special place in my toolbox (works on the engine block drain plug too!!).

Click to expand...

Cut engine oil (straight 30 or straight 40 should do) with Type F ATF (if you can find it,) and fill with that. Replace one pint in the fill, or just cut half-and-half (I don't recall the fill capacity of the BA-10, and I honestly don't feel like looking it up right now. Even though it's in the Tech section of my site. Go check it out - let me know what you think! You have a good excuse now...)

Type F is more detergent than Dexron - it also makes a better ersatz hand cleaner, in a pinch (clean the heavy crud off with the Type F, clean the Type F off with regular hand soap.) However, you can use Dexron if you can't find Type F (you probably can't anymore - it's been replaced by the "Multi-Spec" fluid pretty much.)

Ed - forgot. Run the stuff for about a month and change again. Don't let it go too much longer than that, the ATF can be antagonistic to the seals in the gearbox (they're not designed to hold against that much detergent.)

Thanks. The ATF/oil is a workable and cheap idea. That's the route I'm going to take today. I'm still a bit leery about leaving it in for a month. I was thinking more like about 50 miles of light driving. Then draining and final filling. Nuff said.

I got Pennzoil Syncromesh on the advice of this site, CC.com and my local NAPA guy who said he had a BA10 and ran it exclusively for several years with great results.

My last question on this is after the "wash" there will still be some residue of the mix. Will that adversly affect anything (e.g. dilution) or am I just over thinking this?

BTW: Your tech site is a true GOLD MINE of information and I thank you for putting in the work on it for lazy butts like me. The BA10 capacities are 4x2 - 5.2 pts. and 4x4 - 4.9 pts.

In my case it's fill it until full and give it an extra squirt for good measure before I stick the plug back in.

joe_peters said:

Grabbed this off Yahoo Answers:

"BA-10/5 5-Speed Manual Transmission: Use 75W-90 GL-5 Gear Oil. There are 3 plugs in the tranny. One at the bottom in the rear housing - it's a drain - as always open the fill before draining, just so you can get stuff back in!

Another on the passenger's side above the tranny crossmember - this is the "Fill" and "check" hole.

Yet another on the passenger's side further forward in the main body of the tranny, this is a location for the 5th gear switch (not used by the Renix system) - filling or checking from this hole can leave your tranny almost 1-quart below full -- a VERY common mode of failyure/wear for the Ba10/5 is to have serviced the 5-sp from this switch hole - a medium-duty tranny like the BA10/5 really needs to be well lubricated to perform as designed and low-filling isn't the best way to get these things happy."

Click to expand...

are you sure a gl-5 is ok for the ba-10?

shouldnt it be a gl-3?

89xj said:

are you sure a gl-5 is ok for the ba-10?

shouldnt it be a gl-3?

Click to expand...

As noted, I copied that from Yahoo Answers, without any endorsement.

Does the BA 10/5 have yellow metal synchros?

joe_peters said:

As noted, I copied that from Yahoo Answers, without any endorsement.

Does the BA 10/5 have yellow metal synchros?

Click to expand...

No - the BA-10/5 has aluminum synchroniser rings.

How do I know? I've torn down four of them for scrap metal.

GL-5 is fine for use in the BA-10 - just be sure to switch to GL-3 for the AX-15 (but keep the GL-5 around for the axles, they need it.)

I've done ATF/gear oil before as a gearbox flush, and run it for a month without any trouble. 50 miles isn't anywhere near long enough - if you want to flush it out, go at least 150 (that's about three hours on the highway.)

Yeah, you'll have some residue from the ATF after you drain - but it's nothing that can't be handled once it's diluted.

If you like the Tech side of the site, spread the word! It came about, frankly, because I got tired of answering the basic questions every damned week on all of the boards I'm on, so I just put it all up there.

I'm working on a reorg and addition from electronic FSM/TSMs I've picked up, and I'll be adding a few "Helpful Hint" writeups as I do it. Gimme time...

89xj said:

are you sure a gl-5 is ok for the ba-10?
shouldnt it be a gl-3?

Click to expand...

I had heard - No. I was reccommended to Pennzoil Syncromesh.

joe_peters said:

Does the BA 10/5 have yellow metal synchros?

Click to expand...

I think there is just as much confusion about "yellow metal compatible" manual tranny fluid as there is about Dex/Merc III, IV, V or "multi-compatible" ATF...and whenever I mention "ATF" it's assumed I'm talking about +4 and I'm either chastised for using the wrong stuff (for the record I use Dex/Merc III, IV etc. not ATF+4 in my AW4)

The Pennzoil Synchromesh has no designation on the bottle as to GL-3/4/5. It just says "yellow metal compatible". Now with what 5-90 said about the aluminum synchros my head is spinning. I used his flushing recipe. I'll drive it back and forth to work for 2 weeks, about 400 miles and then re-drain and final fill. We'll see how it works out.

Thanx for the discussion guys.

when i drained the ba-10 on my 89, it sure looked like gl-3 as it had a thinner viscosity then a gl-5.

i refilled with syncromesh thinking i needed a yellow metal safe fluid.

With all of the confusion running around--misprinted owner's manuals, "part dudes" at the retail counter, lube guy at the "$5 Lube and Latte" shops, well, I wouldn't trust any fluid I hadn't put in myself.