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Wheel Alignment For Best MPG


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"The Enterprise" needs wheel alignment (inside edge wear).  Does anyone have the alignment specifications - preferred values and allowed ranges for each parameter both front and rear?  What values would give the lowest rolling resistance?  Have read that the allowed ranges are not just a "tolerance" but there to allow adjustment for preferred handling characteristics.  Would like to have the details before going to the shop.

 

(One F150 owner noted 2 mpg increase after alignment and an Escape owner claimed 4 mpg!  Extrapolating to the C-Max should give, maybe, 6 mpg! happy%20feet.gif )

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"The Enterprise" needs wheel alignment (inside edge wear).  Does anyone have the alignment specifications - preferred values and allowed ranges for each parameter both front and rear?  What values would give the lowest rolling resistance?  Have read that the allowed ranges are not just a "tolerance" but there to allow adjustment for preferred handling characteristics.  Would like to have the details before going to the shop.

 

(One F150 owner noted 2 mpg increase after alignment and an Escape owner claimed 4 mpg!  Extrapolating to the C-Max should give, maybe, 6 mpg! happy%20feet.gif )

No wonder we didn't get 47HWY, all FORD had to do is Align our cars, they would have saved a lot of money. LOL :lol2:

 

Paul

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My guess is that anything that causes the tire to "scrape" more will decrease FE - probably toe-in and then thrust angle more so than camber.  Note that the camber front RH and LH specs are not the same.  The specs are slightly biased for right hand driving roads.  

 

If you are serious about this and the garage is willing to do so, I'd try setting the front toe in to near 0* and the rear toe in such that the total toe in is minimal.  If there is an effect on FE, my guess is this would have the largest effect.  It will be interesting to see how the car tracks with virtually no toe in.  Maybe EPAS will compensate and keep the car going straight. :)  ;)

Edited by Plus 3 Golfer
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Copied from my Ford DVD Service Manual.  Specs shown are for 2013-2014 C-Max Hybrid and C-Max Energi

 

attachicon.gif20150518_090042.jpg

Thanks! Does anyone know what Toe "@ curb ride height" means? I'm guessing "ride heaight @ curb weight", that is, car empty. Hope to get it done this week and, assuning its out, get an idea this weekend about any improvement.

 

+3   I see the front Toe is already 0 and rear is quite small so maybe the standard settings are already optimized for mileage. One would think so.

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Thanks! Does anyone know what Toe "@ curb ride height" means? I'm guessing "ride heaight @ curb weight", that is, car empty. Hope to get it done this week and, assuning its out, get an idea this weekend about any improvement.

 

+3   I see the front Toe is already 0 and rear is quite small so maybe the standard settings are already optimized for mileage. One would think so.

No, here's a better pic of the specs below.  The specs for front toe are between 0* and 0.2*.  So, the techs will likely shoot for around 0.1* toe each side.  What I'm saying is to have them shoot for 0*.  The total toe would be between 0* and 0.4*.  Same with the rear toe but for the rear total toe, the total toe should be between 0.18* and 0.58*.  So it's not possible to set each rear toe to the minimum of -0.01 and meet the total toe spec.

 

Since the vehicle is in essence unloaded when doing alignments, toe at ride height would be toe at curb weight.  But there may be owners that carry significant additional weight in their vehicle all the time.  So, that's probably why it says ride height and those owners should leave the additional weight in the car when doing alignments.  Also, if altering the ride height via suspension or perhaps taller tires, one probably needs to do a new alignment. 

 

gallery_167_32_27078.jpg

Edited by Plus 3 Golfer
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Well I jumped the gun - should have waited for your answer.  Shop had a 3:30 opening today so took it in.

Before | After values are given below (of course a lot of these can't be adjusted anyway):

 

Camber LF = -0.7 | -0.7  RF = -0.6 | -0.6 

Caster LF = 4.6 | 4.6  RF = 4.2 | 4.2

Toe LF = 1/16" | 1/16"  RF = -1/32" | 1/16"  Total Toe = 1/32" | 5/32"  Steer Ahead = 0.09* | 0.02*

(the RF Toe and Steer Ahead were flagged as out of spec)

 

Camber LR = -2.2* | -2.3*  RR = -1.8* | -1.9*

Toe LR = 3/32" | 3/32"  Toe RR = 1/16" | 3/32"  Total Toe = 5/32" | 3/16"  Thrust Angle = 0.05* | 0.01*

 

So it looks like I ended up with more toe in than before!  So much for +6 mpg!

Not sure yet how to convert inches to degrees (crazy system - what's wrong with degrees?)

 

The -2.2* rear camber is near the limit, flagged "yellow" on their system, but that's the one that needs a replacement control arm to correct (gives a fixed +1* correction).  Don't yet have a price but there's some suspicion that it might help the inside edge wear problem (if you call a bit of abnormal wear at 65k miles a problem).  Other option would be to reverse mount the tires half way through their life and re-balance - that costs $60 total.  Paul, how much was the new control arm and how far off was the alignment before replacement?

 

I guess I'll drive these settings for a bit and see.  Then maybe get it redone when new tires go on.  We normally have a total load of about 400 pounds, sometimes more, rarely less.

 

+3, are you saying it would be best to weight the car with a "normal" load and then get it done at 0 toe?  Thanks everyone.

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I haven't seen inches used in alignments for a long time as specs in inches is affected by tire size.   The angular measurement for alignment is accurate not matter what the tire size.  Tire wear as it changes the diameter of the tire will affect the spec (albeit not much) of the alignment when using the "inches" measurement method.  Although I haven't worked through the math, the conversion from inches to angular is:  Total_Toe_angle = atan(Total_Toe_inches / Tire_Diameter).

 

I doubt a several hundred pound will affect the ride height much.  If one was always transporting around the limit of the C-Max, one might want to get the alignment done fully loaded.  I would also guess that if the alignment was near the middle of the spec ranges, the ride height would still be in spec.  But if one was going to shoot for the edges of the spec range (like 0* front total toe in), then when fully loaded one might not see the intended results.  Maybe we can find something "credible" on the net.

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A couple things...

 

Toe-in/out, when I was learning decades ago, was measured to the RIM, not the tire. This seems intuitively obvious when one realizes how easy it is to defect a tire sidewall by 1/32". Accurate measurements can only be taken between hard points. Assume a 8.5" radius when calculating the angle.

 

Statis toe-in must be >0 or you will drive with toe-out. The implied 0.1 degree toe-in is the nominal you should target unless you've replaced all your front bushings with urethane. If a car does not have static toe-in, you will have toe-out on the road, when all the suspension parts are loaded, all bushings deflected, and both front tires slightly behind their rest locations. .

 

Don't get me wrong, toe-out can be a lot of fun. It was a cheap autocross tricks (if you didn't drive far), as a car with toe-out wants to turn. The car is dynamically unstable, just what you want in competition, with trained, experienced drivers, and should avoid in day-to-day driving.

 

But I'm darn impressed with the rear specs; more like semi-trailing arms...

 

HAve fun,

Frank

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There seem to be several options for the rear camber adjustment:

  1. Fixed length replacement arm with +1 degree change
  2. Adjustable arms (seems like the "proper" way to go)
  3. Replacement bolts with off-center bushing (use original arm but may have to cut off a welded on nut)

Any experience or thoughts on the adjustable options?

 

BTW, tried the "shade tree" camber measurement where you stand a level vertical next to the wheel and measure the distance to top/bottom edges of rim.  I got 3/4" difference on left & 5/8" on right with a rim diameter of 18.5" (at measurement point).  Now arcTan(0.75/18.5)=2.3 degrees (considered negative) and arcTan (0.625/18.5)=1.9 degrees.  Exact same numbers as alignment shop!

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  • 2 months later...

Went with adjustable arms that were installed today and the wheels look so much better sitting up nice and straight.  Camber is now about -0.7 (right near the limit) instead of, like, 3 times that amount.  Bought the arms from Massive Speed System, made in USA, purple anodized aluminum (other colors available!) - a shame they're under the car where you can't see them!  BTW, web site may say they don't fit the C-Max but they do - they're on my car right now.  Go get your own set for just over $200.  (No, I have no association with Massive - just delighted to find stuff made in America.)

ey

Now I just need to keep up with tire rotations!  No more "snow tires" in summer!

 

EDIT 2019-03-01 No longer happy with this product!  Had to remove these arms because too much play had developed - wouldn't be able to pass inspection.  Put the old ones back in!  Not willing to throw more money away on a car with 175k+ miles.  I'll just have to put up with any increase in edge wear (or reverse mount the tires half way through their life).

Edited by SnowStorm
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  • 2 years later...

More on inside edge wear problem.  A few months back The Enterprise got new OEM spec tires at 152707 miles.  Went in for the first rotation at 160299 miles.  It looked like there was some inside edge wear starting on the front!  Back tires were fine.  The Michelin Man confirmed this and suggested rotating fronts to back crossed, so direction would reverse, which they did.  My alignment technician looked at the tires and said there really wasn't anything to do (except the rotations) since the front camber is not adjustable!  (I had thought only the back camber was fixed.)  He then said the car companies keep making his job easier and easier as they remove adjustment capability!  Well, I'm getting 70k+ for tire life so there's nothing to complain about.  Maybe I should start putting all the heavy things we often haul around way in the back?

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Direction is reversed with cross rotation but inside edge is still on the inside.  I agree with Paul that (I believe he does this) the best way to even out inside edge wear is to remount the tires flipped on rim so that the inside edge flipped would now be on the outside.  I believe most shops will want $12-15 a tire to remount and balance.  It's not economical to do this every 5k or 10k miles - maybe once or twice say at 25k and maybe again at 50k if there is significant life left in the tire.  I'm assuming this would mitigate the noise issue which for me has been intolerable at around 42k miles in both sets and seems to start nearing 30k miles.

 

I've got about 12 k miles on my third set of tires and the inside grooves are starting to show more wear than the other three grooves.  Using a tire depth gauge, the inside grooves shows between 1/64" - 1/128" more wear.  So, at 50 k miles I might expect close to 1.5/32  more wear on the inside of my tires.  This is very consistent with my previous two sets of tires. I will continue with normal tire rotations and decide when and whether to do the flipped rotation.

Edited by Plus 3 Golfer
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Question: do the front tires wear so much faster than the rear tires that they will straighten out uneven wear that is concentrated on the inside edge ?  Keep in mind that the front tires may also have a lesser negative camber, and the time has to be fast enough that the wear on the rear tires during the evening process is less than or equal to the wear on the tires to be evened out.

 

Question: how soon to rotate from front to back so that the noise of evening out the uneven wear is tolerable ?

 

Question: does the vibration of evening out the front tires exasperate the transmission failure problem of the 2013s and to a lesser extent the 2014-5s C-Maxes ?

 

I did do the reverse mount.  Cost me about $25 each tire.  Noise went away for awhile but it came back before tire wear evened out.  This may not have been the case to the same degree of if I started to put 50 psi in tires when I first bought the car.

 

My current plan/theory is to keep the rear tires on the rear and never rotate them with the idea that eventually I will have tires custom worn to compensate for the camber.  ( I am open to where there may be some holes in that thinking.)

 

When I put new tires on the back, things got so quiet back there that now the front OEM tires sound noisy(not unbearably ) and they are pretty new.

 

I read that negative camber is safer with respect to the car sliding.  But some of that added safety is lost when a portion of the outer edge of the tire no longer is bearing weight.  My sense this is a design problem that Ford managed to not fix.  Perhaps a class action lawsuit may have been needed but somebody has to start it and I was too busy and I would have had to be more aggressive with my service manager who I tend to want to strongly avoid.

Edited by obob
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WOW $25 a tire certainly is not worth it and it really doesn't solve the camber issue.  I guess the other option is to get the rear camber kit to reduce the rear camber.  Looks like about $160 for parts and one hour labor for mounting and then an alignment.  Say around $300+ total.  Should have done this about 3 1/2 years ago and I likely would still be on my 2nd set of tires.  But then what does one set the cambe to?  I don't think I'd go lower than -1/2* to -1* degree.  My rears cambers are -1.4* and -2.0*.

 

I also though of just leaving the rears on the rears but then the question for me is at what mileage does the noise become intolerable?  One might be replacing rears at 35 k miles with maybe another 15k - 25k still on the fronts. I've never liked replacing just 2 tires at a time but have done it in the past.  

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As a datapoint, the noise on my back tires got noticeable at about 60K.  I failed the next state inspection because the belts were showing on the inside corners.

Do you have alignment records as to what your rear camber is?  Also, what speeds are you driving at?   Once I get to 75 mph, the noise becomes intolerable which happened around the 42k+ mile mark on 2 sets of different tires.  At about 70 mph the tire noise is annoying.  At 65 mph it's loud but one gets used to it.  Below 60 mph one can notice it but it's not significant.

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Here is what I have with 77k miles on my OEM tires. I have 3/32 to 4/32 from inside to outside on fronts and 4/32 to 5/32nd's on rears. This is with 50 psi and cross rotating every oil change. BTW I saw a video that it is best to have your thickest tread on the back of car for cornering in heavy rain conditions.  I just got back from trip with heavy rain conditions and MADMAX did fine with marginal tread. :)

 

Paul

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  • 7 months later...

Went with adjustable arms that were installed today and the wheels look so much better sitting up nice and straight.  Camber is now about -0.7 (right near the limit) instead of, like, 3 times that amount.  Bought the arms from Massive Speed System, made in USA, purple anodized aluminum (other colors available!) - a shame they're under the car where you can't see them!  BTW, web site may say they don't fit the C-Max but they do - they're on my car right now.  Go get your own set for just over $200.  (No, I have no association with Massive - just delighted to find stuff made in America.)

ey

Now I just need to keep up with tire rotations!  No more "snow tires" in summer!

 

EDIT 2019-03-01 No longer happy with this product!  Had to remove these arms because too much play had developed - wouldn't be able to pass inspection.  Put the old ones back in!  Not willing to throw more money away on a car with 175k+ miles.  I'll just have to put up with any increase in edge wear (or reverse mount the tires half way through their life).

Went in to rotate tires recently and they found excessive play in these adjustable arms so they have been replaced with the old ones.  Quite disgusted with the product.  Should have just put up with the tire wear I guess.  Nothing like 20-20 hindsight!  Tire shop offed to put in adjustable arms with lifetime warranty (Specialties or Moog I think) but didn't want to spend another $500+ on that option.

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