axle build help. wj swapped 30 and ford 8.8

[smokeyyank]

will changing to a manual trans effect gear ratio selection?
i think i will spring for 4.56 gears, i don't like settling for less.

Yes, manual you can get away with 4.10s auto 4.56 for 33s.

Check out grimmjeeper.com

 

[Dragonlich1961]

Decided on 4.56, rear axle is from a 97 exploder with 3.73 and posi. I know it's not as strong but I need to save $. Front axle is a bit slower. Decided on an artec truss with c gussets and lower control arm brackets.
Using wj tie rod, Clayton/jks. With gm 1ton drag link from ruff stuff. Track bar is still unknown. I have a rusty's bracket and bushing on now. Will probably reuse the frame bracket.
By using the artec c gussests, I'm hoping I can use them as a track bar mount.
Don't know what to use for coil buckets since I will be relocating to achieve proper drag link length.

Any idea on what purpose the factory third shock and upper control arms serve on those explorers.

 

[Heavyopp]

I'm torn between 4.1 and 4.56 too

 

[IslanderOffRoad]

4.56’s with a 5 speed and JK rubi take offs here (about a 32)

I don’t daily drive it but I do love how it drives on the highway

 

[trippled]

I'm torn between 4.1 and 4.56 too

Having had both on the same tires you will regret not going with 4.56.

 

[Heavyopp]

Having had both on the same tires you will regret not going with 4.56.

My problem is I like to take long trips up into NH from NJ -- 4 1/2 hours mostly highway 75 mph

My worry is going 4.56 and getting 9 MPG at 3000 RPM

 

[Dragonlich1961]

33 w/ aw4 &4.56 is 2400ish rpm at 70.
4:11 at the same speed is 2100ish. This is the very bottom of the 4.0 power band. 2400 is nicely in the middle.

 

[XJEEPER]

I've not seen any mention of elevation where the rig is used, the added weight of HD bumper, armor, winch, full size spare, recovery gear, roof mounted racks/tents, puling trailers,etc. None of these factors are ever mentioned on gear ratio calculators, but all reduce the effectiveness of suggested gear ratio.

Odd that no one has mentioned 4:88s with 33's and and AW4.....which is the combo that I've run for the last 10 years/100K+ miles and I've never regretted this gear ratio for a second.

The engine spins at 2800 RPMs at 75mph and I average 16mpg on freeway drives, with 215k miles on the odometer. I live at 4,800 ft elevation and regularly drive up to 9,000ft elevation.

I can pull overpasses and grades in cruise control and my trans stays in OD, whereas with my last XJ with 33's and 4:56's/AW4, the trans was constantly hunting between 3rd and OD on slight elevation increases.

Too many people go too tall (numerically lower) on their regear because they are afraid that lowering their gear ratio another step will kill their fuel economy. The reality is the opposite.

 

[XJEEPER]

My problem is I like to take long trips up into NH from NJ -- 4 1/2 hours mostly highway 75 mph

My worry is going 4.56 and getting 9 MPG at 3000 RPM

See above for real-world numbers....... :thumbup:

 

[Heavyopp]

See above for real-world numbers....... :thumbup:

Thats an interesting post above -- I wonder what happens to those numbers at sea level to 3000 feet?

 

[XJEEPER]

Thats an interesting post above -- I wonder what happens to those numbers at sea level to 3000 feet?

Operating at sea level to 3000 ft means the air is more dense, so the engine will make more power, which requires less throttle/fuel consumption to move the rig down the road.

If one looks solely at how gear ratio affects fuel economy, the amount of applied throttle (fuel consumed) to get the rig moving down the road/maintain cruising speed is more impactful to MPG than cruising RPM.

I've run 4:56's with 33's/5 speed and 4:56's /AW4 and my experience is that 4:56's/33's are great with a 5speed, but not low enough gearing with an AW4.
On a prior XJ, I was running 4:56's/5speed/33's, but swapped out the BA10/5 manual for an AW4 auto and after the trans swap, my rig felt like my axle gear ratio was back to 4:10's.

The trans would constantly shift out of OD into 3rd on the slightest grade, would hunt between 3rd an OD when cruising and I was required to apply a lot more throttle to get the rig up to speed and maintain cruising speed, which resulted in a 3-5 MPG loss in fuel economy.

I've experienced none of these issues running 4:88 gearing, which has been awesome with an AW4 and 33's.

 

[techno1154]

Operating at sea level to 3000 ft means the air is more dense, so the engine will make more power, which requires less throttle/fuel consumption to move the rig down the road.

If one looks solely at how gear ratio affects fuel economy, the amount of applied throttle (fuel consumed) to get the rig moving down the road/maintain cruising speed is more impactful to MPG than cruising RPM.

I've run 4:56's with 33's/5 speed and 4:56's /AW4 and my experience is that 4:56's/33's are great with a 5speed, but not low enough gearing with an AW4.
On a prior XJ, I was running 4:56's/5speed/33's, but swapped out the BA10/5 manual for an AW4 auto and after the trans swap, my rig felt like my axle gear ratio was back to 4:10's.

The trans would constantly shift out of OD into 3rd on the slightest grade, would hunt between 3rd an OD when cruising and I was required to apply a lot more throttle to get the rig up to speed and maintain cruising speed, which resulted in a 3-5 MPG loss in fuel economy.

I've experienced none of these issues running 4:88 gearing, which has been awesome with an AW4 and 33's.

Your real life experience with the XJ and various combination of tire size, gear ratio and transmission is food for thought. In my other post this evening on Cal's build we were talking about the same thing,...gear ratio verses tire size. I must admit, I have never driven a XJ with a manual transmission. However, I find the AW4 with 3.55 gears and 30" tires leave a bit to be desired. The same could be said about my present configuration of 4.10 gears and 32" tires.

I just ( 2 hours ago) completed a trip from Orlando to Jacksonville some 150+ miles driving my Toyota with a manual five speed. The first 20 miles out of Orlando on I-4 reminded me why I will never buy a manual shift vehicle. The Toyota was a gift that is very reliable and gives 27+ MPG everyday. Try driving 20 miles in 40 minutes in rush hour traffic shifting 1, 2, 3 then coming to a complete stop then start the process all over again.


I agree with everything you said and others should take it literally. I think I will regear to 4.56 and consider it a perfect compromise between city stop-and-go and highway driving.

 

[Dragonlich1961]

Ford 8.8 is installed, iron rock off-road kit worked perfect with truss, with one minor problem, it looks like the truss was made an 1/4 inch to long, meaning the u bolts were hitting it during install. Nothing a grinder couldn't fix.

Question regarding brake cables, what are people using.
My stock cables are sticking on one side due to rubbing the exhaust, so running cable clamps is not an option. This is for a 94, so will a zj cable work?

 

[Dragonlich1961]

axle swap is done, and i couldn't be more happier.
Jeep stops and steers better than factory. no more bumpsteer and toe change with suspension cycle. Jeep handles bad before especially on gravel roads. Now i have confenece that the jeep will go where i want it, my main goal since my fiance will be foring med feild soon so reliable 4x4 transportation is a must.
Old brakes were subpar and bad design, with pads riding straight on the knuckle leading to grooves, and barly stopped the jeep before. New brakes are nicer and easier to service, and are doing some seroius work on my 33*12.5. they will lock in rain, snow, or gravel. I have heard them barking under hard braking on dry pavement, soming never heard form the old brakes. (i am running a 96 booster and a ford 8.8 with discs.)
Curernt setup is atrec truss and c gussests with tnt coil buckets, g2 4.56 gears with open diff,(i know) ruff stuff 1 ton steering kit, offset TRE'S and high angle drag links. IRO unit bearing spacers and caliper spacers with stock 94 hubs and redrilled wj rotors centered the caliper corectly. Wilwood system use shims as well to acheive proper spacing so i have no concern. i did have to buy longer caliper bolts, which are hard to fine because they are considered super fine thread.
Artec truss and c gussets fit flawlessly and look awsome, also ordered there upper poly mount kit.
Tnt coil buckets worked ok and allowed me to shift the coil spring back to allow for a proper trackbar. they are sold for 2.75 tube and dana 30's are 2.5.
Ruff stuff sterring kit worked flawlessly. Offset TRE's barely contacted my wheels which are 15*8 w/3/75 bp. Grinder to remove a 1/16 and they clear at full lock. 1.5 inches between stock diff cover and the 1.5inch DOM.
Drag link and trackbar are the same length, angle, and only 4 degrees from level. In order to do this the trackbar is mounted inside the passenger C live on Cal's race rig. Using a 7/8 3/4 heim and dom(3/4 grade 8 bolt mounted in double shear). body side is a rusty's trackbar bracket modifyed to move the mounting point in-word. Trackbar, draglink, and tierod are all made from the two pieces of dom from the ruffstuff kit. Draglink tube is only 19 inches long. Total length is 33 inches~.
Swaybar mounts are inspired by curry and other high steer kits and are welded to the inner C's. Super tight fit on passenger side due to trackabr location. they are a cut down rough country kit.
brakes are 04 units (akbeno) and they clear my wheels with 3/16 to spare, no grinding required.
I'm currently maxing out my shocks with the spring unseating an inch, but i can still unseat the spring another 3 inches with the shocks un hooked, on IRO short arms.
running a set of bilsteins F/R. no stering bind.
Those with brake lines close to being to short, the brake lines mount lower in the wheel and there for reduce the amount of free play you have, mine are to short to wheel with once proper shocks are sized.