ftpiercecracker1

PeteM: "What about just rebuilding yours? I've read it's pretty easy as transmissions go. it might just need new synchros." Its my only means of transport so I have to have it back on the road as quickly as possible. No time for my f**k ups. I've never opened up a trans before much less rebuilt one, nor do I have the (special) tools or space to take on such a task. I've watched a ton of videos on rebuilding an ax15 over the years and it's not simple. If this was a toy I would give it a go, but in my situation I can't afford to. This needs to be as quick a turn around as possible. Tex06: "The AX-15 is pretty easy to rebuild although personally it sounds like your clutch isn't fully disengaging anymore. I would recommend swapping to a new external slave and see if it fixes the issue before investing in a new tranny." With the truck in gear and the clutch disengaged (pedal pressed down) the truck doesnt move and doesn't try to move. Doesnt that mean the clutch is close to if not 100% disengaged? As far as internal vs external slave. I know the external is easier to replace, but isn't the internal slave better in terms of mechanical advantage? Pushing straight vs using a pivoting arm.

Not sure what I am going to do about that yet. Whatever is cheapest probably.

Why would you intentionally buy a rebuilt transmission that the seller admits was rebuilt incorrectly and doesn't work right? I'd rather get one from a junkyard with higher miles and a 90-day warranty. The ad says it pops out of second on occasion. I figured if i got i could spend another hundered bucks or two to have 2nd gear fixed and i would have a freshly rebuilt nv3550 for $700. To optimistic?

What do you think of this one? https://sarasota.craigslist.org/pts/5997140358.html

Even if it has 150k?

Re-clocking a t-case will require drilling and taping something yes?

Well the clutch seems to work fine hydraulically, never had an issue with pressure leaking down. The pedal has always engaged and disengaged smoothly with good return pressure. Not really sure how a bad clutch system could cause the problems I am experiencing, especially with 3rd gear.

I have an MJ with the AX-15 and my 2000 XJ has the 3550. There is no question -- the 3550 is BY FAR smoother than the AX-15. You can't even really compare them. The AX-15 feels like the gears were carved by hand with a sledge hammer compared to the 3550. I bought the 2000 XJ new, and I fell in love with the transmission before I had driven five miles from the stealership. What is your opinion on where I should look for a nv3550? JY or internet(ebay) rebuild?

Grinding between almost every gear if you don't rev match perfectly. Third gear grinds especially bad and will attempt to slot in without the clutch or rev matching resulting in spectacular grinding. Third gear is becoming harder to find and today the transmission briefly got stuck in third gear for the first time. Extreme clutch chatter because the pilot bearing has been nonexistent for at least the last 30k miles. Which I will assume has destroyed my input shaft/seal. I did a very through trans flush about 15k miles ago. Probably the first one it's ever had, fluid was the most putrid rank vile smelling stuff you can imagine. But no metal. Flushed it twice with motor oil, then filed it up with Redline MT. I give 100% credit to redline for extending the life of the transmission this long and will definitely be using it on my next trans.

Would you rather have an AX-15 or NV3550? Would you rather get an original one with 150k out of a junkyard for $500 or a 0 mile 'rebuilt' one for $1000? The ax-15 in my truck is going to go any week now and i need to figure out what i am going to do before it leaves me stranded. I like the NV3550 because it has a deeper 1st, taller 5th, and a synchronized reverse (i think). But i've been reading that shifting the 3550 can notchy/crunchy. Which ever is the smoother shifting transmission is the one i want. Also from what i have read the NV3550 is a direct bolt in, is this correct? Thanks FPC

Higher nickle content so the story goes, I think, no idea how such a claim could be verified. Supposedly it extends the life of the cylinder bores a fair amount. But on the other hand HO blocks incorporated more webbing cast into their blocks which provided improved rigidity. Which one is best? The world may never (care to) know.

4th

because OEM expansion tanks break easily? or that an engine like the 4.0 doens`t need it? why break what is already fixed...? The first part is true, I'll give you that, but I don't follow the second part. Doesn't need what? And just to be clear I said that because I thought your system was working as is, if not my mistake.

For simplicity sake I think it's hard to beat an open system. don't have to worry about bleeding it just so or having all the extra pressurized plumbing that could spring a leak. That being said, I still have the closed system. Had to buy one new pressure bottle and upgraded the cap to the Volvo unit. Also deleted the HCV. I have had this setup for years now and have never had a problem. The truth is, all things being equal, the closed system actually has a larger coolant capacity. The only benefit I see to switching would be for convenience and a little more simplicity. Why fix what ain't broke? FPC

Good news, the chances are those cheap oils you are using are fine, and actually are possibly better than some of the more expensive oils that people throw in the 4L. Any source on this? I find it hard to believe cheaper oils are better than more expensive. Maybe not worse, but why would they be better? Because guys use all sorts of weird stuff that isn't for a gas engine, or isn't the right weight (or even close), or race oils that aren't designed for long life, or has way too much zinc in it, or they throw crap additives in that are at best not helping anything. https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/ Shell Rotella T6 ranks #162 on the list, yet guys love running it. Spend a day reading that if you want. I stand by my first comment that cheap oil is totally fine. He should probably be changing it more often, but the economics are totally up to him, and if his leak/burn/filter change rate is high enough will be fairly new anyways. To build on what DirtyComanche said, I think that the cheaper oils are better in the sense that they are better for the 4.0 specifically, not that they are of overall superior quality than the more expensive oils. Every oil is engineered for a specific environment, run what is called for and don't fall for the pretty advertisements and sales gimmicks. The 4.0 is one of the most abuse tolerant engines made, so long as your close and its topped up it won't matter. They same argument is commonly made pertaining to spark plugs. The conciseness around here seems to be that the cheap Champion brand copper core plugs are what 4.0s like best and its been that way for me. Just because it costs more doesnt mean its better for your particular application. I will say this, that if you do run cheap oil you should always keep it topped up and change at more regular intervals/less mileage . . . . . . . . . . . yes I'm aware of the irony/hypocrisy. Like my momma always said "Do as i say, not as i do" As someone already said always, always run a good filter. This i feel should be stressed. Fram had a serious problem with filter media/pleats collapsing starving engines for oil and causing catastrophic engine failures. I imagine this problem has been solved, but it was enough to scare me away permenatly and to be highly suspicious of any engine outfitted with one. FPC.

Everyone talking about this or that specific oil/weight, ZDDP, shear mechanics, etc and here I am dumping whatever I can find that's slippery into mine. Lol. But seriously, I just use the very cheapest 10-40 I can find with a good quality Wix/Mobile 1/Napa gold filter. Although, I have on several occasions just used whatever motor oil I have laying around to top it up when needed. I am currently researching ways of adding oil capacity. Since I use such cheap oil and rarely change it. Current oil must have around 11k on it. I did change the filter somewhere in between. She leaks/burns enough oil that its hard to justify changing it at regular intervals. Even so, she still has great oil pressure at 250k and she just keeps on purring.

There is a kid on here who is almost done doing that very swap PLUS a turbo. If he doesnt see your thread and comment himself, I will try and get you a link to his build. Edit: Here ya go, probably everything you could want to know about a 3.4 swap. Lots of pictures too. http://comancheclub.com/topic/49436 It's been a while since I checked his progress, sadly the 3.4 went boom in a big way. He tried another one which ran great, but then the transmission went boom. Now he is switching back to original equipment 4.0/ax-15 combo

For an 88 4wd: http://www.rockauto.com/en/moreinfo.php?pk=2950014&cc=1179839&jsn=407 For a 90 4wd: http://www.rockauto.com/en/moreinfo.php?pk=4218006&cc=1179996&jsn=464 For anyone interested the link for the 1990 speedo cable works great. Just installed it tonight. 1990 4.0 AX-15 combo It feels REALLY cheap, so I'm not sure how long it will last, but it's better than not having one at all. Thanks again Dirty!

I will definitely be looking into this. Will report back with my findings.

But i thought if you tried to use an XJ sender with an MJ gauge it would read backwards?

Interesting, I had no idea. Thanks for the link.

If that is true and the XJ gauge will just plug and play, then it would only be a matter of adapting the XJ sending unit to the MJ fuel tank.

My sending unit is fubar from my tinkering. So I would have to get an entirely new set up. Which is fine because my current sending unit leaks fuel anyway. One of the metal tubes that protrudes out of the metal flange is cracked around the weld. It was my understanding that the XJ fuel sending unit was incompatible with the MJ fuel gauge. Which would mean getting a new XJ gauge, but I don't know if that would create more problems. Are MJ and XJ fuel gauges interchangeable? If I can buy a new XJ fuel sending unit and modify it to work in my current fuel tank, then get a XJ fuel gauge to match, it seems that would be the best course of action.

What leads you to believe it has a D44? I also would like to know what they are asking. Looks like a good specimen.

Cable ordered. Thanks for the link, now I just hope it's the right length. From what i know, BA10 and AX15 used two different length cables. All I have is what the truck came with stock. Fuel tank is new but its a few years old now. I am open to any possibility, so long as it is not overly expensive. You think a budget of $150 would be enough?