AX-15: alternative options?

[jeepcoma]

I remember finding a great page about all sorts of transmission info but can't seem to find it now. Anyway, my question is, are there any alternatives regarding gear ratios in the stock AX-15? Since switching from 3.07 to 3.55 gears (and stock sized tires with no plans to change) I'm frustrated by how low 1st gear is and how wide each shift is. 1st is pretty much useless except for getting rolling (which I realize is the point of 1st but I feel like I have to shift at 2-3 mph); if I need any sort of real acceleration I really have to wind it up each gear to 4k-ish so the revs don't drop too low when shifting to the next gear; engine braking is pretty much pointless as I never get down below 3rd; the throws are also long and clunky with difficulty engaging.. Conversely though 4th and 5th are pretty useful on regular roads and the highway, I'm never lacking for power on the highway in 5th and it's really in the sweet spot when going fast enough to put the revs around 2500.

 

Stock AX-15 I google is listed below, are there any close ratio or "sporty" options I could swap in? Wouldn't mind dumping the internal slave while I'm at it.

 

First Gear 3.83

Second Gear 2.33

Third Gear 1.44

Fourth Gear 1.00

Fifth Gear 0.79

[Geonovast]

Uhhh... not really. First gear with 3.55s should not be that bad. Try driving a 2.5 sometime.

 

3.55 or 4.10 with a 3.93 first gear.

 

You could(bleh) swap in a Pukey. All the ratios are the same, except the pukey sports a 3.39 first.

[jpnjim]

Uhhh... not really. First gear with 3.55s should not be that bad. Try driving a 2.5 sometime.

 

3.55 or 4.10 with a 3.93 first gear.

 

You could(bleh) swap in a Pukey. All the ratios are the same, except the pukey sports a 3.39 first.

 

 

I've had 4 Peugeot's (yeah, glutton for punishment :wavey: ),

and all have had either 4:1(ish), or 3.80:1(ish) first gears.

 

The two 87's had the lower 4:1's, and the 88 & 89's were slightly taller

(ratio measured by marking input & output shafts, and counting rotations, with the trans removed from the Jeep).

 

 

Maybe someone here has actually measured a BA10-5's first gear ratio at the 3.39:1 ratio I always see listed/published,

but I think it was a mistake/misprint, or different application (Peugeot car maybe?) that somehow still lives on in almost every 4x4 Magazine, and website I've looked at. :dunno:

 

 

 

 

To the OP, most of the jeep 5spds have that very similar gear spacing.

The 6 spd has an even lower first.

 

Closest overdrive I can think of to what you want is they used a Ford Toploader 4spd overdrive trans in some 1980's Ford F150's.

4th became the overdrive, and I'm pretty sure first was taller than the typical 4:1.

It bolts to a 4.0L with a Tremec/Jeep bellhousing (T-176/T-150), but doesn't have the window for our CPS.

[jpnjim]

Closest overdrive I can think of to what you want is they used a Ford Toploader 4spd overdrive trans in some 1980's Ford F150's.

4th became the overdrive, and I'm pretty sure first was taller than the typical 4:1.

It bolts to a 4.0L with a Tremec/Jeep bellhousing (T-176/T-150), but doesn't have the window for our CPS.

 

Wow, tough to find info on these overdrive Toploaders (usually called the 3spd O/D, or RUG trans for it's serial numbers).

 

It's probably not a good swap, but interesting to dig info up on anyway:

 

thin cut, non-performance gears,

Cast iron 'truck' version:

 

Ratio: 3.29 1st, 1.84 2nd, 1.00 3rd, .81 4th, and 3.29 Rev.

 

 

Aluminum 'car' version:

 

Ratio #1: 3.29 1st, 1.84 2nd, 1.00 3rd, 0.81 4th, and 3.29 Rev.

Ratio #2: 3.07 1st, 1.72 2nd, 1.00 3rd, 0.70 4th, and 3.07 Rev.

 

and another truck version identical to Jeep T-170 series (but with O/D gears)

 

Ratio #1: 3.01 1st, 1.78 2nd, 1.00 3rd, 0.79 4th and 3.01 Rev.

Ratio #2: 3.25 1st, 1.92 2nd, 1.00 3rd, 0.78 4th and 3.25 Rev.

 

 

http://www.5speeds.com/toploader.html

 

 

other links:

 

http://www.motivegear.com/tech_info/tra ... guide.html

 

http://www.davidkeetoploaders.com/imposters.htm

 

If it would hold up, I'd actually like one of these for the Javelin. :yes:

[jpnjim]

I know I'm the only one here that cares about these O/D Toploaders,

but this guy in Ohio has a pile of them for $200 each (2wd):

 

http://northeastoh.ebayclassifieds.com/ ... ad=3247319

 

* Ford Toploader overdrive 4 speed transmissions- Granada / F150

* Address:Akron, OH 44305 (map)

* Date Posted:06/24/10

 

Description now have four left of the toploader 4 speed overdrive transmissions from 1970's Granada and F150 applications, these units will fit behind 289, 302, and 351 applications, $200 each transmission, buy one or all for a package deal...(330) 784-6088, thanks for looking!!!

 

[jeepcoma]

Try driving a 2.5 sometime.

 

Hmm.. no thanks. When I lived in Australia my wife had Daihatsu 1.3L 5-spd... and that was the sporty model (you could get a 3 cyl 1.0L auto trans with A/C :eek::ack: ). It was fun though, we'd load it with three passengers and weeks worth of camping gear way over GVWR and head though 1000 km straight through roads that reminded me of the Tail of the Dragon here in the US. Was fun though, short throw shifter, smooth clutch, close ratios... that's what I want now. Even loaded as it was, it had plenty of power to pass big rigs going up hill on shared 2-lane roads, if you kept it in the powerband.

[jeepcoma]

If it would hold up, I'd actually like one of these for the Javelin. :yes:

 

What type of Jav do you have? I have a '73...

 

[Pete M]

Jeepcoma, what size tires are you running?

[jeepcoma]

225/75/15

 

I was thinking of putting larger tires on to reduce the overall ratio back to where it was before (which would also fix the speedo/odo since I never swapped the speed sensor), but it seems more of a bandaid than a cure.

[mkbruin]

Have you looked at nv3500 or 3550? Auto-swap?

[Eagle]

I remember finding a great page about all sorts of transmission info but can't seem to find it now. Anyway, my question is, are there any alternatives regarding gear ratios in the stock AX-15? Since switching from 3.07 to 3.55 gears (and stock sized tires with no plans to change) I'm frustrated by how low 1st gear is and how wide each shift is. 1st is pretty much useless except for getting rolling (which I realize is the point of 1st but I feel like I have to shift at 2-3 mph); if I need any sort of real acceleration I really have to wind it up each gear to 4k-ish so the revs don't drop too low when shifting to the next gear; engine braking is pretty much pointless as I never get down below 3rd; the throws are also long and clunky with difficulty engaging.. Conversely though 4th and 5th are pretty useful on regular roads and the highway, I'm never lacking for power on the highway in 5th and it's really in the sweet spot when going fast enough to put the revs around 2500.

The "best" tranny for the XJ and MJ is generally considered to be the NVG 3550, and that has a much lower gear than either the Peugeot or the AX-15. The ratios are 4.01 - 2.33 - 1.39 - 1.00 - 0.78. You don't seem to appreciate that Jeeps are not sports cars, they are trucks. First gear, as you pointed out, IS for getting started. I have the NVG 3550 in my 2000 XJ and with stock tires for street driving I find it to be far superior to either the Peugeot or the AX-15.

 

As to the last sentence I quoted above, with 3.55 gears and stock tires, 2500 RPM is approximately 80 MPH. With both the Renix and HO vehicles, I don't consider 80 MPH to be the "sweet spot." I do think the factory 3.07 gearing was a mistake, but with 3.55 gears and a 5-speed things seem to be pretty close to a good, overall compromise.

 

Hurst makes a short throw shifter for the AX-15. You can get it from Summit Racing.

[Pete M]

225/75/15

 

I was thinking of putting larger tires on to reduce the overall ratio back to where it was before (which would also fix the speedo/odo since I never swapped the speed sensor), but it seems more of a bandaid than a cure.

 

bandaid? tires are a part of your overall ratio and should be in any calculations. :thumbsup:

 

30x9.5s on 3.55s worked great for me.

 

I hope you're not trying to make a car out of a truck. :hmm:

[jpnjim]

If it would hold up, I'd actually like one of these for the Javelin. :yes:

 

What type of Jav do you have? I have a '73...

 

 

Looks nice man,

I like the full vinyl tops. :thumbsup:

 

I'm also digging the silver paint on your headlight surrounds.

don't think I've ever seen that done before.

Really makes the headlights pop. :cheers:

 

 

Mine is a Humpster too,

71 Javelin/AMX.

 

P-code 360/4bbl (ignore the 401 bagdes ;) ).

Cowl hood, Go-Package, 3.91/Twin Grip (71's still used the old style Power-Lok, instead of the later Trac-loc's)

V-code 4spd (close ratio 2.23, 1.77, 1.35 & 1:1 gears).

 

 

 

I've owned it for almost 20 years (Sept 92 pic:)

 

It was originally Green/Green:

 

I swapped a complete 71' black interior w/leather buckets in when my little brother painted it for his Senior Project in high school.

 

Car has 99k miles on it,

current engine is a slightly built 360, +.030, forged pistons, 9:1ish, General Dynamics cam, Torker, 780 Holley, cheap blackjack headers & 2" duels.

 

I really want to swap the 3.91's out, and start driving it again,

but it doesn't look like I'll be putting it on the road this year.

 

Do you drive yours, or is it just a parking spot place holder like mine?

[jeepcoma]

You don't seem to appreciate that Jeeps are not sports cars, they are trucks.

 

Crap! I knew I was missing something... :doh: The irony is Jeep's "Sportruck" model... :yes:

 

As to the last sentence I quoted above, with 3.55 gears and stock tires, 2500 RPM is approximately 80 MPH. With both the Renix and HO vehicles, I don't consider 80 MPH to be the "sweet spot."

 

Merging into highway traffic or street driving, 3k rpm in 2nd, 3rd, or 4th gear is pretty common in order to get moving. So no, I don't run at 80 MPH on the highway, but cruising at 65 mph is right around 2250 RPM where the engine is just starting to make power. It has noticeably better passing power in 5th gear at that speed than if you back down a bit to 2k.

 

I do think the factory 3.07 gearing was a mistake, but with 3.55 gears and a 5-speed things seem to be pretty close to a good, overall compromise.

 

I do agree the 3.55 gearing is much better than the 3.07s, it's just not what I consider ideal. Is it wrong to want to improve my Jeep to suit my liking?

 

Hurst makes a short throw shifter for the AX-15. You can get it from Summit Racing.

 

Thanks, will check it out! :thumbsup:

[jeepcoma]

225/75/15

 

I was thinking of putting larger tires on to reduce the overall ratio back to where it was before (which would also fix the speedo/odo since I never swapped the speed sensor), but it seems more of a bandaid than a cure.

 

bandaid? tires are a part of your overall ratio and should be in any calculations. :thumbsup:

 

30x9.5s on 3.55s worked great for me.

 

I hope you're not trying to make a car out of a truck. :hmm:

 

Maybe "bandaid" was the wrong word, I mean I'd be back to the original performance characteristics and gear ratio spreads, which is what I'd like to change.

 

Besides, so what if I want to make it more car-like (which I don't). I thought the great thing about Jeeps was customizing them to make them uniquely yours. My MJ is a street work truck that sees a lot of pavement. I want to improve its performance in the areas it makes sense to me, so I'm not interested in huge lift and big tires and the usual (I'll have to get a second MJ for that :D ); if there was an easy and inexpensive transmission swap that had better ratios for my intended use, I'd jump on it. I guess the short answer to my question of a sport transmission option is "no, there isn't".

[jeepcoma]

Do you drive yours, or is it just a parking spot place holder like mine?

 

Nice Jav. Mine is a very low-buck bare-bones 304 with the three-speed (on the tree) 998, open rear end, drums all around, nothing fancy. I have a few semi-vintage go-fast parts on it, dual-point distributor, 4-bbl carb and intake, baby cam to swap in when I get around to it...

 

Haven't been driving it much, though I did drive it pretty frequently a while back. Had a brake line pop, parked it for a bit until I fixed it. Radiator sprung a leak, parked it for a bit until I fixed it. Charging system went, parked it for a bit, then my brother parked his Mustang in front of the garage door and blocked it in. Did some traveling, got married, bought a house, spent all my money, got other projects to work on, yadda yadda car has been sitting just waiting for a money infusion. Need to replace some trim pieces around the windshield, and to be honest I'm more afraid of other drivers on the road than anything else when I take it out, so for the time being I'm content to let it sit in the garage knowing its glory days will come again in the not too distant future.

 

Started like this...

[comanche09]

I'm running an AX-15/3.55 gear/31" tire combo.

 

Yesterday, I climbed a steep 1/8 mile long mud/bogged hill in 1st gear and 4HI with a 250 4-wheeler in the bed and 10ft trailer with 500 4-wheeler on it in tow. I like the steep first gear. :yes: (could be a little steeper). Held her at 3,000 RPM all the way up.

 

It was all or nothing as there would be no backing up! :eek: Had to get as best of a running start at possible, but was tough with my BFG A/Ts caked with wet mud acting like slicks. The old girl powered her way to the top. Temp gauge reaching the halfway mark. Score 1 for my 'Manche

[benjy_26]

A world-class T5 or a Tremec T56 *should* bolt up to a 4.0 using the AMC Gen III V8 adapter parts. I'm not sure how much work would be involved, but seei g as how those V8's and the Jeep inline 6 share a bolt pattern, it seems feasable and should get you quicker, closer shifts than the AX tranny. Will those trannies mate to a transfer case? I honestly don't know.

[gogmorgo]

You realize you just resurrected a 3.5 year old thread, eh?

[benjy_26]

Not until after I posted, unfortunately. I was looking up info on tranny's and this one popped up. Saw the dates after I pulled the trigger. Sorry.

[randomguy310]

I might be wrong but it should of gotten better going to 3.55 from 3.07 gear that a lower ratio.