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Replace AW4 with Manual?

BSD

BSD

NAXJA Forum User
Location
OKC
Looking for advice. I have an 89 4.0 XJ with the AW4. My neighbor has a dead XJ, same year I think , with a five speed manual. I am thinking ahead and wondering if I should salvage his tranny and think of swapping it in when - or if - the AW4 ever dies. What motivates me is gas prices. Does teh manual get much better mileage? I would think so. Any thoughts.
BSD
 
BSD said:
Looking for advice. I have an 89 4.0 XJ with the AW4. My neighbor has a dead XJ, same year I think , with a five speed manual. I am thinking ahead and wondering if I should salvage his tranny and think of swapping it in when - or if - the AW4 ever dies. What motivates me is gas prices. Does teh manual get much better mileage? I would think so. Any thoughts.
BSD
Click to expand...
No most cases less.
 
The EPAs little chart says the manual gets better mileage (by about 3 mpg) I get almost 21 with my 90 MJ with 3.07s stock. If its a 89, it might be the pukegoat. Which you would NOT want to swap in.
 
summitlt said:
The EPAs little chart says the manual gets better mileage (by about 3 mpg) I get almost 21 with my 90 MJ with 3.07s stock. If its a 89, it might be the pukegoat. Which you would NOT want to swap in.
Click to expand...
EPA mileage is a mathematically calculated estimate. The AW4 full lockup transmission will give better mileage on average because it’s consistent shift points. The Manual transmission mileage is more driver dependant. The other thing is the AW4 is a very very strong transmission.
 
langer1 said:
EPA mileage is a mathematically calculated estimate.
Click to expand...

You're actually wrong on that. They stick a vehicle on a "track" in a lab and simulate terrain and then round it down (they have a formula for doing so).

Anyways, if you wanna swap the manual in it's not that hard, just make sure that the 89 doesn't have the peugot transmission (I forget which year they went to ax15).
 
Kejtar said:
You're actually wrong on that. They stick a vehicle on a "track" in a lab and simulate terrain and then round it down (they have a formula for doing so).

Anyways, if you wanna swap the manual in it's not that hard, just make sure that the 89 doesn't have the peugot transmission (I forget which year they went to ax15).
Click to expand...


In actual driving for me atleast the auto averages about 4 mpg more. I ahve a 4.0 5 speed and 4.0 auto. The auto is in an xj and the 5 speed in the MJ, (it is lighter and never has a tailgate to restrict air flow) The auto just does better around town and for all oaround typical driving
 
Kejtar said:
You're actually wrong on that. They stick a vehicle on a "track" in a lab and simulate terrain and then round it down (they have a formula for doing so).

Anyways, if you wanna swap the manual in it's not that hard, just make sure that the 89 doesn't have the peugot transmission (I forget which year they went to ax15).
Click to expand...
True they do now, but in 89 they were allowed to do both and submit the best one to the EPA..
 
I still think with the right driver, youd get better mileage witht he manual. You also have more gears to let the engine have more range. Although the TQ could do that also.
 
You also decide what gear to use and where engine RPM is going to be at any given time so. With a manual I think people are more tempted to drag the gears (remain longer in a lower gear) but you have the potential to use stay longer in lower gears for power or upshift sooner. Plus you can just pop it into neutral and coast up to stoplights. No, its not what youre "supposed" to do but I frankly don't care. Also I have heard pickups inherently get less milage than suvs because theres more to the aerodynamics difference than the tailgate but I'm definetly not an expert on this.

I say if you want a 5 spd and are willing to do whats involved with the swap than go for it. If you want it and have a donor vehicle w/ ax-15 get it in there as the opportunity may pass. I love my having a manual tranny (factory) in my XJ and I would be far less attracted to XJ ownership in the first place if this were not an option. I don't usually find it burdensome (even though my master cyl is going out). I am a bit saddened actually by the dominance of auto trannies in the U.S.
 
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bajacalal said:
I say if you want a 5 spd and are willing to do whats involved with the swap than go for it. If you want it and have a donor vehicle w/ ax-15 get it in there as the opportunity may pass. I love my having a manual tranny (factory) in my XJ and I would be far less attracted to XJ ownership in the first place if this were not an option. I don't usually find it burdensome (even though my master cyl is going out). I am a bit saddened actually by the dominance of auto trannies in the U.S.
Click to expand...
Well said :D mine came with an ax15 from factory and then when I rolled it I swapped all the ax15 stuff to an aw4 rig I picked up.
 
Kejtar said:
...just make sure that the 89 doesn't have the peugot transmission (I forget which year they went to ax15).
Click to expand...
Yeah, the AX-15 is much better than the Peugot tranny. They began using the AX-15 mid-production for the '89 model.
 
its not just swapping out the tranny for this. You will need to accomidate the sifter inside. You would need to relocate the ebrake and you will need to do lots of cutting. The demensions dont match.
 
helix said:
its not just swapping out the tranny for this. You will need to accomidate the sifter inside. You would need to relocate the ebrake and you will need to do lots of cutting. The demensions dont match.
Click to expand...
? a swap of an aw4 for an ax15 doesn't require all that. It's pretty much a drop in solution. I know, I did it.
 
Kejtar said:
? a swap of an aw4 for an ax15 doesn't require all that. It's pretty much a drop in solution. I know, I did it.
Click to expand...

I know wtf... I thought the parts list was limited to:
clutch and brake pedal assembly thing + bracket, eliminate NSS switch
the clutch master & slave cylinder
shifter stick, boot, related parts, console bezel? (the e brake is farther back)
ax-15 tranny mated to the same t-case you have w/ reverse switch the clutch parts (obviously)
flywheel (make sure its right for your model year), driveshaft
tranny mount, cross member (unsure of this don't remember)
missing something?
 
bajacalal said:
I know wtf... I thought the parts list was limited to:
clutch and brake pedal assembly thing + bracket, eliminate NSS switch
the clutch master & slave cylinder
shifter stick, boot, related parts, console bezel? (the e brake is farther back)
ax-15 tranny mated to the same t-case you have w/ reverse switch the clutch parts (obviously)
flywheel (make sure its right for your model year), driveshaft
tranny mount, cross member (unsure of this don't remember)
missing something?
Click to expand...
You have this pretty much right.
If it's an aw4, the crosmmeber and tranny mount is the same.
It's good to have the tcase linkage and bracketry as those are different and they line up different (you need both the body side and tcase side IIRC).
 
Kejtar said:
You have this pretty much right.
If it's an aw4, the crosmmeber and tranny mount is the same.
It's good to have the tcase linkage and bracketry as those are different and they line up different (you need both the body side and tcase side IIRC).
Click to expand...

Oh yeah. I remember something about the T case is going to mount to a slightly different angle too on the tranny.

If you pull the neighbors tranny make sure you get the ax-15. The Pug Ba10-5 can be split lenghtwise like a hot dog bun down the middle. Its 2 halves bolt together. The AX-15 only opens at the ends so the middle section is a solid piece. So, its easy to tell them apart. Also theres the AX5 which looks a lot like the AX-15 but isin't as strong. The AX5 was used only in 4cyl XJs so there you go. If youre neighbor got a 4.0 and it doesn't have a seam down the bottom youre good to go.

Edit: http://www.jeeptech.com has some pics and info under the transmissions and engines pages.
 
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I'm surprised to hear people getting better mileage with the AW4, given that a person with a manual knows when to shift... and mine even has a little light to remind me when to shift. :) I have the AX15 in my 97 and I'm getting as good as 27 mpg highway with the 4.0. Is anyone with an AW4 getting mileage like that? I went with a manual because of gas mileage, and because I love driving with one. The only thing I hate is that I can't tow nearly as much as an XJ with the AW4 and a towing package.
 
sgtpeeper said:
I'm surprised to hear people getting better mileage with the AW4, given that a person with a manual knows when to shift... and mine even has a little light to remind me when to shift. :) I have the AX15 in my 97 and I'm getting as good as 27 mpg highway with the 4.0. Is anyone with an AW4 getting mileage like that? I went with a manual because of gas mileage, and because I love driving with one. The only thing I hate is that I can't tow nearly as much as an XJ with the AW4 and a towing package.
Click to expand...
you get 27 mpg on the highway? are you sure you got the right speedo gear? or are you constantly going downhill???
 
Yeah, I really am getting that kind of mileage. I've read of other people on here getting the same mileage with the same setup as my XJ. Honest! :) But like I say, that's highway. I've been somewhere in the lower 20's city. I usually stay 5 mph over the speed limit on the highway. My Honda get's 39-40 mpg highway when I keep the speeds reasonable, but when I drive 85 mph, well.....
 
sgtpeeper said:
I'm surprised to hear people getting better mileage with the AW4, given that a person with a manual knows when to shift... and mine even has a little light to remind me when to shift. :) I have the AX15 in my 97 and I'm getting as good as 27 mpg highway with the 4.0. Is anyone with an AW4 getting mileage like that? I went with a manual because of gas mileage, and because I love driving with one. The only thing I hate is that I can't tow nearly as much as an XJ with the AW4 and a towing package.
Click to expand...
Is that actual mileage or from the MPG thing on the overhead council. Either way that’s way higher than normal.
 
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