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Front Axle Upgrade Help Part #1

How To: Convert a Front Axle

Our Project Land Cruiser has seen more swaps, mods and changes than we ever thought it would. Every time we thought it was at a point where we could leave it alone and simply enjoy it, something bigger, better, faster or stronger came along. Call it evolution, call it envy, call it keeping up with the Jones’, call it masochism – it is what it is and that’s just the way we are.

It all started when we decided that our beefed-up, Birfield-impregnated FJ40 front axle just wouldn’t be strong enough to handle 35″ meats (reliably that is), not to mention our prototype steering just wasn’t cutting the mustard. It was now time to install an axle up front that would be cheap, tough, easy to maintain, easy to find parts for, and easy to repair on the trail.

This isn’t an instruction set for converting axles, nor will we go into details on why we chose our ’78 Jeep Cherokee Dana 44 front axle, except for the fact that the spring puches were the same width as the stock FJ40; it’s not that type of article. What we will cover, are some questions you should ask yourself and all of the little gotchas that we ran into when swapping out axles, even on a rig that’s relatively barren of gadgets that would make the install tougher (e.g. anti-lock brakes, coil-sprung suspension, anti-sway bars, sensors, etc.).

Before you decide to convert a front axle, here are some things to consider:

  1. Axle width – will you have to cut and axle down, or can you go with a standard width?
  2. Axle width 2 – If you are thinking of going to a wider axle up front, will the local terrain be an issue? (e.g. are the trails too narrow?)
  3. Steering – will you have a problem with the tires rubbing against the frame, shocks, shock mounts or spring at full lock?
  4. Spring purch location – will the spring purch / spring buckets (spring mounting points) be in the same location, or will you have to modify the axle and / or the spring locations?
  5. Brake lines – will you have to modify your brake lines to make them fit? Will they need to go from metric to standard (or vice versa)?
  6. Steering components – will you have to change from a front-to-back steering system to a cross-over steering system, or something different?
  7. Wheel bolt pattern – can you reuse your rims, or will you have to modify your axles to accept the bolt patterns? Or do you have the bling-bling left to buy 5 new wheels (no 22 inch spinners aloud!)?
  8. Condition of axle to be swapped in – will the axle have to be completely rebuilt? Is the housing straight and true?
  9. Gear ratio – will the gear ratio match that of your rear axle, or will you have to install new gears too?
  10. Strength & Size – What type of wheeling do you do? Do you need a big ol’ Dana 60, or will a 44 cut it and save precious ground clearance?

This isn’t an exhaustive list of questions, but some to at least get you pointed in the right direction. Ask fellow wheelers what works for them. Contact a reputable 4-Wheel Drive company that has years and years of experience such as Stage West 4-Wheel Drive Center or All Pro Off Road. These folks have forgotten more about building and wheeling rigs that most of us will ever know. Ask their opinions and thoughts, but most importantly, do lots and lots and lots of research. It will be worth it in the end.

After we received our front axle from Stage West 4-Wheel Drive Center, we enlisted the help of Tucson Differential to build the innards to our specifications. With a fully assembled axle, it was time to start the process of fitting it to our Cruiser. Swapping an axle requires some patience, a checkbook, a good set of tools and a good mechanical mindset.

Tools you should have (aside from the standard wrenches, sockets, etc.):

  • Welder
  • Angle finder / gauge
  • Torque wrench
  • Hub socket
  • Brake line tubing bender
  • Brake line double-flaring tool
  • Large drill bits (1/2″ to 7/8″)
  • Torch (we did our swap without one, but…)
  • Reciprocating saw
  • Upper-ball joint keeper socket
  • Large C-Clamps
  • Drill press
  • Heavy duty hand drill with large chuck

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