Bad News

Joopin

Super Moderator
I posted about my jeep making noises and such about a week back. Some of you said it may be idler pulley, which seemed to make sense to me. Well I got it checked out so I didn't go changing stuff for nothing. The mechanic told me he thought it was the transmission. So I called Cottman, told them about the whining and grinding noises in 3rd 4th and 5th... he automatically said... sounds like bad "Higitty shmiggity Rods"... I don't know what they were but it was greek to me since I have no clue about manual trannies.

Bottom line he said he can't really do a diagnostic without getting INTO the transmission to see what is wrong with it cause its a stick. Not to mention Jeep doesn't make parts anymore for these I guess... so he made it sound like my only option was to get a new one... which he in turn said it would be 2k for a new AX-15 installed.

So now I have a 4.0 with 213,000 + miles on it, with a sporatic leaky rear main, and a bad transmission. If I were to get both engine and transmission rebuilt it would easily be $4,000. I don't know what to do. I am wondering what it would cost to drop a 350 drivetrain in this sucker. Any thoughts? If not that's fine, I'm just venting in a way. :x
 

What if I get a junkyard jewel? Is there an upgrade I can do that will bolt up to my 4.0 and NP231? Or should I just get another AX-15?

I found this, but I'm not going to an auto.

http://www.4x4wire.com/jeep/tech/trans/yj700r4/

But the article does drop some models in there that could work... [FONT=Verdana,Arial,Tahoma,Helvetica,Helv,sans-serif]the SM420, SM465, and the NV4500. I have no idea what they are out of or if they are manual trannies. I assume they would need an adaptor somewhere. Anyone know about a swap like this?
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All three you just mentioned were from Chevrolet trucks. I believe Muncie made the 420 and 465. The NV4500 was made by New Venture. I believe they are the same people who make your New Process transfer case. All three have ideal low gears in first and are bombproof. It would kind of defeat the purpose to put one of those monsters in front of an NP231, but it has been done.
If you were happy with the Ax-15 then I would say score one from a junkyard and make them give you a 90 day warranty on it. Put it in yourself and save some dough.
If you want an upgrade, the NV4500 from the three above would be the best choice. The other two are fine for the woods but don't shift very smoothly and would be annoying to drive on the street all the time. I think you could probably score a newer NV3550 from a TJ. I don't know a lot about them though.
Lots of choices here. I would look into the 3550 and then make the decision. I definitely would not pay $2000 for Bobo to take apart an AX15 when you could probably score one for $150.
The good news is that you can fix the leaky rear main when you pull the transmission. Just drop the oil pan, remove the bearing cap and replace the seal. There's a little more to it, but it's not that hard.
 
I actually googled those trannies, and the NV4500 is the only one that is a 5spd too as far as I can tell. I don't really know what vehicles they came out of other than Chevy / GM trucks from 1993 and then into Dodge trucks in 1995, but didn't find out till when... they still use them?

I never thought about a TJ donor... so I assume the NV3550 would bolt up with no need for any adapters right? Do the TJs use the NP231? I dunno if I could put in a transmission myself since I only have a driveway and no lift besides the one on my jeep. I gotta find somebody with a lift.
 

if you want to do the rear main seal, talk to m. its still fresh in my mind from when i did mine and my girlfriends.
 
You can still get parts for an AX15, but a rebuild is often the most costly option. A junkyard swap is cheaper, but also risky.

You may try changing the fluid out to Redline MT90 (as long as you can still use each gear in your transmission). It's a full synthetic that does great in the Aisin Warner AX manual trannies, it's easy on the synchronizers.

Drain your fluid and check it out. If it looks like glitter, then your synchronizers are going out and a replacement would be your best option. Otherwise put in the Redline.

Shoud you go the junkyard route, be sure you use the Redline. My AX5 had 125K on it when I installed it and, with the Redline MT90, it shifts smooth as silk even in the coldest of weather.
 
Bounty__Hunter said:
You can still get parts for an AX15, but a rebuild is often the most costly option. A junkyard swap is cheaper, but also risky.

You may try changing the fluid out to Redline MT90 (as long as you can still use each gear in your transmission). It's a full synthetic that does great in the Aisin Warner AX manual trannies, it's easy on the synchronizers.

Drain your fluid and check it out. If it looks like glitter, then your synchronizers are going out and a replacement would be your best option. Otherwise put in the Redline.

Shoud you go the junkyard route, be sure you use the Redline. My AX5 had 125K on it when I installed it and, with the Redline MT90, it shifts smooth as silk even in the coldest of weather.

Did that, it was shifting hard about a year ago. Bought the Redline, shifted smooth as silk. The guy that checked it out even said that the fluid looks new. The Cottman guy asked what I put in it when I called them. I told him redline and he said that a synthetic sometimes makes it worse for old trannies cause it's almost TOO slippery and it may have been part of my current problem.
 

if money issue, swap in a new to you ax-15.. you can find then on craigslist cheap. I swapped on in for a friend that he got about three years ago for like $200, we also put in a new clutch, TB, and re-surfaced his preasure plate, and is still running to this date.

If you try to swap something in.. the amount of money and down time will be a lot greater, so if you have the time and money, put a nv 4500 in. you will get a 5 spd transmission with over drive as well as a granny low first.
 
"Too Slippery..." That's funny and evidence enough of reasons why you should not take the Jeep to him.
Yes the 420 and 465 are 4 speeds. I think the NV4500 is still used. I know we had a 2000 or so model Chevrolet at work that had one. They are usually pretty pricey though. Probably $800 to $900 plus adapters.
You should be able to install a transmission in your driveway with the help of a friend and a jack. Just don't try to put the transmission and transfer case in together and it makes it considerably lighter.
You can also buy a cheap scissor style transmission jack for $80 from Harbor Freight.
Most junkyards will give you a 90 day warranty on parts, but verify first.
 

Yeah I was looking at that Navak site earlier, they have info on many transmissions, what is needed to match up to what engines... really good stuff.

John hit it on the head though, unfortunately it is about money. Especially since I have been trying to pay off my credit card which had some of my Parnelli Jones' and a BMW that I backed into... I would have money saved up for this project if I didn't have that BMW front end to pay for. Oh well. I think I am going to look for another AX-15 or a TJ transmission, that way I can get something with hardley any miles on it (compared to mine) and it's a direct bolt in. Wait, is the NV3550 a direct bolt in?
 
nv3550 or used ax15. the 420 is obsolete as far as parts go, but the np435 is a great transmission :D (its only a 4 speed)
 

Joopin said:
Did that, it was shifting hard about a year ago. Bought the Redline, shifted smooth as silk. The guy that checked it out even said that the fluid looks new. The Cottman guy asked what I put in it when I called them. I told him redline and he said that a synthetic sometimes makes it worse for old trannies cause it's almost TOO slippery and it may have been part of my current problem.
I've heard of the 'too slippery' problem before but it doesn't apply to the Redline, it's specially formulated to work properly with the soft brass synchronizers of the AX5 and AX15.

If it shifts smooth, and your fluid looks like new, I wouldn't be too quick to sign the death cert. on the transmission.
 
is there another oppinion you can get?

id agree, if you start cheap and just plan to do a tanny oil change, you may find you are OK.

while your under there lube every zirk you can find.

whine in higher gears, could equate to whine to at higher speeds, not ness. transmission. could be bad bearing in the rearend, slight tweak or off ballance of the drive line. either one could add extra unneeded stess and pressure of the trany and/or transfer case (which may be a good one to drain and check as well)

another option that would earn you the bravery badge. you know the tone and pitch of the noise its making. pull of the wheels put her on jack stands or heavier duty than jackstand blocks. fire her up and roll under there with the largest flat screw driver you have. put the butt of the driver up to your ear and the spade end to various suspect parts. you will be able to hear what and where the problem is through the screw driver (even over the running vehicle). sounds silly and archaic, but it saved me a transmission and with all the extra money i "saved" i slapped a push button locking rearend from a prerunner into my 2wd minitruck.(feel privilidged, that was the first time i ever called her that)

when did the simptoms start? just out of the blue or maybe a post wheelin trip?

id hate to see you put 100's in someone elses pcket just to find a diagnosis from a part swappin mechanic tryin to make a buck.

once they get the trany swapped and have you under the impression the car is imobilized in their shop. (aka they got ya by the short and curlies)

"welp that wasnt it, yeah the problems deeper than we thought the "sch****** flargen bearing is out to" were gonna have to change that to"
 
Did you ever verify it was a transmission problem? This thing started with a bad idler pulley. Just run it til it lets go. Then you will know what the problem was.
 

Okay, I just got a call from the guy that test drove it. It's a mechanic right down the street from me, I picked him cause he was working on an old scrambler and a 1947 army jeep when I was in there... hopefully he knows his stuff.

He told me to rebuild the transmission it would be 800 bucks plus the parts needed and would take 4-5 days.

I asked him "How do you know it's the transmission and not something else"
He pointed out that if it was the idler pully, the noise would be there in every gear, (not just 3rd-5th like it is now) cause the pulley is turning the whole time. That same reason is why it's not in the T-case, rear, or engine.... which makes sense. The noise only happens when my foot is on the gas in 3rd-5th. He said there are bearings for each gear and he said they are going bad slowly but surely... 2nd is starting to have a slight noise too.

Oh and tint rookie, the higher gears and higher speeds thing makes sense, but if I have it in 4th going as slow as I can go in that gear it still makes the noise, RPMs don't seem to matter.

So It looks like there is still a good chance it's the transmission, I am going to get one more guy to look at it to make sure.

Oh and I got another quote from a guy saying he would do a swap for $400. But it would have to be direct bolt in.
 
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