Front Wheel Bearings - Towing & Tools
 

I had a front wheel bearing go out at the track last weekend. I'm planning on carrying spares, tools and torque specs now. I just started trailering my Miata to the track.

1. Do you soften your front shock settings when putting the car on a trailer?

I saw on the Spec Miata board that they attributed some failures to trailering the car with repeated stress at the same place on the bearing. They don't have adjustable shocks but I do.

2. What type of punch or cold chisel do you use to bend the nut back out of the spindle groove?

I can't find a flat cold chisel narrow enough and the round punches don't seem to work well.

I just use a large screwdriver to unbend the nut. It's thin and soft. Not a big deal.

Rock Auto had front hubs in the sub-$30 range. For that price, pick up a few and have them on hand.

I usually use an impact, but when I don't have air available the tab never seems to stop a long breaker bar with an even longer cheater on the end of it.

Yeah, I just stick the socket on the big impact gun and let it spin it off, that unbends the tab just fine.

--Ian

I don't tab the fronts. Never had one come loose. The nut doesn't rotate like it does in the rear (the rears definitely come loose if you don't stake them).

Hm. I think I'll go out and check mine right now. :)

--Ian

Some of those electric impacts are actually pretty good. They take off wheel lugs. Not sure about an axel nut though

Yeah, I realized this spring I had done 4 days last year without the nuts staked. Never backed off, still had the proper torque.

If your impact can't break 150-175ft-lbs, it's junk.

This from the man who told me to use a set of halfshafts that had the staking grooves ground away. I'm not feeling the love . . . .

Hmm, is the Rockauto "PRO Part # 29513155" the ticket (ABS version)?
I can get four of those for the price of one Hub locally, including the shipping (which is 55% of the total from Rockauto).
I have even found a local source for Amsoil Dominator/2000 grease :) (I have not had a failure with Redline CV2 but if Amsoil is better why not try it)

If you worry about the shocks on the trailer, do as some formula guys do, put the car on blocks and strap it tight (i.e no changing load on the tires/hubs/shocks) or replace the shocks with dummies for transport (requires resetting of setup, but if you worry this much you probably would do that anyway).

To the trailering question, I know of a few formula car guys that block the frame so that the shocks are completely unloaded while in the trailer. That may be excessive, but then again the Penskes on my S2 aren't behaving right and I don't have enough weekends on them to believe they need valve servicing due to on-track wear and tear. Maybe the shim valves on racing shocks are more vulnerable to this sort of wear?

A simple breaker bar should be able to break it. Simple as pulling up. 200 lb pull should easily break it. As far as the chisel goes, grind one so its flat on the sides so it goes in the grove and fat the other way. A 6mm open end wrench works alright for this too but a specifically ground chisel will be better of course (hold the wrench with vice grips while you hit it).

on NB1s the front is 29mm, the rear is 32mm and tight as hell. I had to cut the rear nut to get it "off". Broke 2 wrenches with no luck.

Are you strapping the car down by the wheels or the chassis?

Still using U-Haul open trailers, the fronts have straps over the wheels. That's why I'm thinking not having the shocks at full hard might mean a little less stress on the front wheel bearings.

I really don't think it would make much of a difference either way. The suspension is only dealing with up/down movement of the sprung weight of the car, which should not place much stress on the bearings.

I've always loosed up my shocks as much as possible while towing, only for the odd chance that it would reduce wear and tear on the shock absorbers themselves. My logic is that they aren't working as hard to control body motions.

I'd think that the wheel bearings and shocks would see more stress on track than being strapped down in a trailer.

Exactly in a trailer that also has a suspension. Not sure how far you plan on driving but 2-300 miles IMO wont be a problem. Take a look at the pro racing teams, All the cars are ready to run with the final change being the tires. No difference for air plane transfers.

How the guys on the Spec Miata board explained it was on a trailer there is repeated stress on the same place. On track the stress is distributed to many different places.
The U-Haul trailers I'm renting have springs. My longest drive is around 550mi each way.

Whether its the trailering or track time, I'm carrying spares and tools now. I just don't want to cause replacement unnecessarily.

In school they taught us to put a tractor inner tube under the car with a piece of plywood on top of the tube. Load the car, air the tube up, and unload the suspension. Adding shocks to the trailer is also supposed to save the shocks on your car.