Background: I am finishing up a suspension refresh on a 93 XJ. I am about to replace the upper/lower balljoints, tie rods and drag link; at that point every wear item in the suspension front and rear will have been replaced. Also I have recently installed some 245/75-16s on 2016 Wrangler wheels with adapter/spacers (read about it here)

I have been researching DIY alignment techniques and have found many great resources. All seem to agree that 1/16 to 1/8 inch toe in is desired for most XJ's. However, there doesn't seem to be much consistency on from where exactly to measure that difference.

Examples:
1. This site, go.jeep-xj says to measure "...between the front tyres on the widest part both front and rear". ON THE INSIDE OF THE TIRE ON THE SIDE WALL.

2. In this Bleepin Jeep youTube video , measurements are made at the ends of some metal angle iron pieces attached to the tires. ON THE OUTSIDE OF THE TIRE PAST TIRE EDGES.

3. And this site, 4x4xplor uses tire tread lugs to make measurements. ON THE TREAD OF THE TIRE.

4. And then there is this technique from wranglerforum where tires are removed and metal tubes are clamped to the brake rotors and measurements are taken from them. TIRES OFF, TUBES ATTACHED TO ROTORS.

If toe were being set to zero degrees I can see that it shouldn't matter, and all of the above techniques could provide similar results.

But doesn't WHERE the 1/16 to 1/8 inch is measured from, ultimately affect what the actual toe in ANGLE is?

 

I did midway up the tire in the rear (where there's no tire change from the weight/psi) and same spot in the front. Rides fine but haven't had it checked by an official machine or anything.

 

Find a way to mimmick the usefulness of this or buy it.

 

The important part is to make sure that you are measuring from about the same height front and rear. I usually measure the rear first, so I get as far up as I can against the LCA's, as far against the sidewall where the tread cuts in (I have MTR's), then move to the front and eyeball the height and push it forward until I hit tread again. (If I street tires, I would probably just measure from the center tread to the center tread.)

Perfect? No. Good enough? Yes.

 

Honestly any method you prefer can work if done right. Just make sure your making consistent measurements. I have used inside of tires and angle iron on brakes. About 1/8 toe in has been right.

 

Thank you guys for the feedback. I guess my issue is that an 1/8 inch measured in different places won't produce the same degree of toe. I was wondering if there was some type of spec or official process that called out the "right place" to measure the 1/8, 1/16 or whatever... Sounds like you guys are saying that in the end, the differences are negligible.

 

I take a drywall screw and run it through a thin piece of wood at an angle.

Jack up each front wheel and spin the tire scribing a fine line in the center of the tire.

Use the line to measure from

 

I measure from a **** on the tire that holds a tape measure well to its corresponding **** on the tire on the other side, both front and back, and aim for somewhere between 1/8 to 1/16th. If I notice any pulling to either side or less-than-smooth riding I'll pull over and adjust it a little bit until it behaves the way I want. (I find a half turn of the adjusting sleeve to be a good amount to adjust at a time for fine-tuning.)

So far I've put about 14k miles on my MTs and the wear has been surprisingly even.

 

me too. i've been doing it this way for many years and i used to work in an alignment shop where we used to scribe a chalk line in the center of the tire tread, much like what cruiser was describing. works much better and easier.

 

Very similar to what I do. Only difference is I spin wheel and hit it with white spray paint on center of tire tread and then scribe line in fresh paint. I put a nail 3" nail in a piece of wood and lay it on floor and move to the wheel while spinning, gets a good fine line. Paint wears off in a few miles.

 

Even better!!

If you're hot scribing a line, you're at risk of doing a poor job.

 

What are the members' thoughts on front end off the ground vs. on the ground?

Did mine with the vehicle raised and notice some feathering and outer shoulder wear after 1000 miles. Re-adjusted with weight on the front and though I haven't had it on the highway yet, seems much easier to steer.

 

On the ground!!