Troubleshooting NV3550 to Novak AX15 swap

[msmall007]

Hello. Novice here, looking for help. 2003 TJ 4.0L. Swapped out fried 3550 for Novak AX15. Along the way… new rear main seal, new LUK flywheel and cutch. Stayed with stock rear mount and shifter. Learned a lot on what is a big project for me, but didn’t think I made any mistakes….

Filled AX15 with fluid today, started engine for first time in 6weeks, released cutch for first time … there’s nothing there. No feeling of engagement…no drive. I’m not sure where to start now honestly.

There was some confusion over the transfer case (NP231) input gear… Novak included a short they said I’d likely need, but after measuring what I had, i reasoned I did not. TX case and AX15 joined together fine. I assumed if this had been the case, a ‘too long’ input gear would have kept TX case and transmission from joining?

I hear nothing when letting out the clutch…. Except in reverse, where I hear either throw out bearing noise (similar to what I remember hearing errors before in other vehicle). Maybe that was actually the sound of the transmission in reverse and nothing’s getting into the wheels??

Would appreciate any advice on where to start. Frustrated as I thought I was done

 

[machoheadgames]

A long input gear fits fine and is not the problem. The factory equipped long gears on at least 98-99 AX15 Jeeps.

You sure your transfer case isn’t in neutral? Shift lever plate on transfer case oriented correctly (facing down)? Didn’t forget to reinstall the driveshaft?

 

[mrblaine]

You sure your transfer case isn’t in neutral?

That first, then verify the rear driveshaft is turning.

 

[Rickyd]

Does the clutch pedal have resistance like it is compressing the clutch?

What do you mean "stock shifter"? Did you put an nv3550 shifter onto the ax15?

Can you feel and hear the transmission going into each gear?

 

[msmall007]

A long input gear fits fine and is not the problem. The factory equipped long gears on at least 98-99 AX15 Jeeps.

You sure your transfer case isn’t in neutral? Shift lever plate on transfer case oriented correctly (facing up)? Didn’t forget to reinstall the driveshaft?

I’ll check anything. I know the TX shifter is down (the shift handle in the cab I mean)… so assume they to not in neutral… but I will check.

Drive shafts are definitely in place.

 

[machoheadgames]

I’ll check anything. I know the TX shifter is down… so assume they to not in neutral… but I will check.

Drive shares are definitely in place.

Make sure the shift lever plate is facing down. Make sure that it is NOT facing up like this. If it is, flip the plate to go downward.

My initial post said facing up, but I have corrected that. I get mixed up because other models have it up.

 

[msmall007]

Does the clutch pedal have resistance like it is compressing the clutch?

What do you mean "stock shifter"? Did you put an nv3550 shifter onto the ax15?

Can you feel and hear the transmission going into each gear?

I totally feel clutch pedal resistance.

I was referring to the ‘kit’ Novak sells with a turnkey AX15… it included a cable-based TX case shifter which is supposed to be smoother. I opted not to use it right now as the stock linkage seemed to mate up correctly.

I don’t know that I feel the transmission changing gears… there’s no resistance so unsure. I’m far too used to depressing the cutch to change gears with out doing so. I’m not sure I can tell by feel that the transmission is turning.

 

[msmall007]

Make sure the shift lever plate is facing down. Make sure that it is NOT facing up like this. If it is, flip the plate to go downward.

My initial post said facing up, but I have corrected that. I get mixed up because other models have it up.

View attachment 637305

Almost home… need to check that! I don’t recall changing anything on the TX case, but need to look at my before pics.

 

[machoheadgames]

Almost home… need to check that! I don’t recall changing anything on the TX case, but need to look at my before pics.

Well, you probably didn’t change anything intentionally but you may have put the arm back upside down. It’s easy to do.

You had to deal with the shifter one way or another to get the transfer case out.

 

[msmall007]

Well, you probably didn’t change anything intentionally but you may have put the arm back upside down. It’s easy to do.

You had to deal with the shifter one way or another to get the transfer case out.

It feels like the TX case arm is definitely the issue!!... I don't know what the position is supposed to be, but here are some pictures of what I have right now. These pics (not great) are with the TX shifter in 2H position in the cab.

 

[Rickyd]

I don’t know that I feel the transmission changing gears…

Engine off you will notice the shift gates and it going into each gear. Reverse being harder than the others.you used a Novak shifter for the ax15?

The transfercase being in neutral and/or transfercase linkage misadjustment is easy to figure out. Only one position out of four will free wheel.

 

[msmall007]

One more

Engine off you will notice the shift gates and it going into each gear. Reverse being harder than the others. You used a Novak shifter for the ax15?

The transfercase being in neutral and/or transfercase linkage misadjustment is easy to figure out. Only one position out of four will free wheel.

Yes... I can tell, with engine off, the transmission is moving into separate gears.

When you say "You used a Novak shifter for the ax15?"... I guess I need to clarify what you mean. I am not using the cable-based TX shifter that came in their kit... I needed to get my Jeep back on the road sooner than that side-project would allow, but do plan on installing it someday. I am using the same OEM TX case shifter linkage.

I am using the Novak shifter stick... it is the only think I have that will fit on the AX15 shifter tower. It is not super drivable like this though as going into 1st, 3rd or 5th, the stick hits the dash.... I need to bend it I know.......

 

[Rickyd]

With the jeep and transfercase solidly in a gear can you roll your jeep or turn the rear driveshaft if it's on stands?

With the motor off?

 

[msmall007]

With the jeep and transfercase solidly in a gear can you roll your jeep or turn the rear driveshaft if it's on stands?

With the motor off?

I do appreciate the trouble shooting, I have not taken thee jeep off the wheel cribs yet…. But will before continuing.

 

[machoheadgames]

It feels like the TX case arm is definitely the issue!!... I don't know what the position is supposed to be, but here are some pictures of what I have right now. These pics (not great) are with the TX shifter in 2H position in the cab.

View attachment 637329

View attachment 637330

It’s hard to tell based on the pic but I think you got the adjustment for the shifter off. I think your t-case is in neutral while your shifter is in 2H.

Your best bet is to disconnect the linkage and shift the transfer case into 2H manually and see if things work properly from there. Then you can adjust the shifter until it connects to the t-case without shifting it and keeps the lever in the 2H position in the cab.

 

[msmall007]

Thank you all for your help. It was the transfer case,... very much a rookie mistake. I was not paying attention to the linkage connection... the slotted connector was not even all the way on the transfer case 'key'.

I have a bigger and more depressing problem though. When I first had transmission issues I relied on the opinion of a reputable (or highly rated) local transmission shop. They are the ones that told me my transmission was fried. Their estimate is what lead me down the $3k decision to do the job myself. Now I have the new transmission in... and I am having the same experience as before. I do not think my transmission was ever the issue.. I think it was all in my transfer case. I should have come on here with questions on how to diagnose myself. F..... I need a drink and I don't anymore...

 

[machoheadgames]

Thank you all for your help. It was the transfer case,... very much a rookie mistake. I was not paying attention to the linkage connection... the slotted connector was not even all the way on the transfer case 'key'.

I have a bigger and more depressing problem though. When I first had transmission issues I relied on the opinion of a reputable (or highly rated) local transmission shop. They are the ones that told me my transmission was fried. Their estimate is what lead me down the $3k decision to do the job myself. Now I have the new transmission in... and I am having the same experience as before. I do not think my transmission was ever the issue.. I think it was all in my transfer case. I should have come on here with questions on how to diagnose myself. F..... I need a drink and I don't anymore...

What issue have you had all along? A bad noise or something?

 

[msmall007]

Well, I guess I have a lot to learn… I had a neighbor come over which I wish I would’ve started with and watch the Jeep and listen to the sound that I’ve been experiencing. It looks like it’s been the differential all along. I heard the noise and rightfully, I thought, took it to a transmission place for diagnosis, and they told me it was the transmission and likely also the transfer case. The experience that I had before replacing my transmission, which granted based on the metal filings on the drain plug certainly probably needed replacing anyway, is exactly this one…. Will add video later from my computer.. on iPad now and cannot attach video.

 

[msmall007]

Well... I hate apple... here at least is the audio. Basically..,. when you hear the sound you see the driveshaft spinning at the read differential. I can't believe a reputable transmission place would not realize this.
View attachment 637793

 

[machoheadgames]

Well... I hate apple... here at least is the audio. Basically..,. when you hear the sound you see the driveshaft spinning at the read differential. I can't believe a reputable transmission place would not realize this.
View attachment 637793

I hate it for you, but this is why I despise shops. Always get a second opinion if relying on shops for diagnosis. Or phone a friend who knows a bit about cars and give them some cash or something to do their own diagnosis.

If you can open up the rear axle and see what is actually wrong, maybe it is repairable to some degree. Or maybe you can find a cheap axle on car-part or Facebook.