What size rear wheel spacers suggested?

michaels86svo · Post by **michaels86svo** » Tue Mar 21, 2006 8:48 pm

I've seen in peoples signature at different size rear wheel spacers.I've seen from 1" upto 2" spacers. The rear measures only 1" narrower than the front but see the 1.25" are the most popular.Can you give me some before/after pics and reasons for decision for your choices?

Post by **Walt** » Tue Mar 21, 2006 10:51 pm

Although the front track is only 2" wider overall (1" per side), our CC's have an Isuzu bed, which has fender bulges on each side, further emphasizing the narrower rear track. IMO, if you want the rear tires to line up perfectly with the fenders, just like the front, go with 2" spacers in the rear. It's all up to personal preference. I run 2" spacers in the rear, and before I got new wheels and skidz flares, they lined up perfectly with the rear fenders, so you'd never notice that the rear was wider.

killian96ss · Post by **killian96ss** » Wed Mar 22, 2006 7:31 am

I think a lot of people are running 1.25" spacers because they didn't know that 1" spacer will fit. The front track is 2" wider than the rear, so when you put 1" spacers on the rear then you have the same track width as the front. Personally I wouldn't want my rear track wider than the front due to the turning apex. Almost all vehicles have a slightly wider front track than the rear for this reason and to help tire wear. If you rear track is wider than the front your tires will wear a little faster and there is a little more stress on the front suspension pieces. There is a reason car manufacturers design the front/rear track this way. Now that I have said that, I would like to point out that it is perfectly safe to have a wider rear track if that's what you like.

Steve

Post by **HenryJ** » Wed Mar 22, 2006 5:03 pm

killian96ss wrote:... I wouldn't want my rear track wider than the front due to the turning apex. Almost all vehicles have a slightly wider front track than the rear for this reason and to help tire wear. If you rear track is wider than the front your tires will wear a little faster and there is a little more stress on the front suspension pieces. There is a reason car manufacturers design the front/rear track this way...

Too many things to dispute. I'll just let this one alone.

jeff024 · Post by **jeff024** » Wed Mar 22, 2006 6:03 pm

if you just wanna even things up go with a 1.25 spacer on the rear and call it a day

killian96ss · Post by **killian96ss** » Wed Mar 22, 2006 9:22 pm

HenryJ wrote:
killian96ss wrote:... I wouldn't want my rear track wider than the front due to the turning apex. Almost all vehicles have a slightly wider front track than the rear for this reason and to help tire wear. If you rear track is wider than the front your tires will wear a little faster and there is a little more stress on the front suspension pieces. There is a reason car manufacturers design the front/rear track this way...
Too many things to dispute. I'll just let this one alone.

There really isn't anything to dispute!

Talk to any good alignment tech and they will tell you the same about why the front track on almost all cars is wider than the rear. Car manufacturers design the track this way for the optimum turning apex. Everybody has there opinion on certain things and in fact I didn't believe the whole thing about the turning apex the first time I heard it, but after listening to a few well know alignment techs from Infineon Raceway and my own personal alignment tech, I can tell you for sure that they all agree on this one. Brule, even though you don't agree with my statement about turning apex's, I would still like to hear your opinions on this subject.

Steve

Post by **HenryJ** » Thu Mar 23, 2006 5:12 am

I'd like to hear why the tire wear will be increased and why matching the track width will increase stress on the front suspension components. (Don't forget we do not have spooled axles)

killian96ss · Post by **killian96ss** » Thu Mar 23, 2006 10:00 am

I will try to explain this as best as I can.

There are a few reasons that the front track width is wider. #1, the turning radius is better. #2, tire wear is decreased. #3, it allows the rear tires to follow the front tires through a turn. When you rear track is wider than the front your rear tires are not following the correct turning apex which results in the rear tires being slightly dragged through the turn instead of following the fronts. This is similar to having an incorrect toe adjustment. Too much toe in or out has the effect of dragging the tires sideways increasing tire wear and suspension stress. The toe only needs to be off 1/8" for this tire wear to occur. When you have 4 tires fighting against each other than you are increasing tire wear and suspension stress. Tire wear is the biggest factor here. The extra suspension stress in minimal, but it is still there. My explanation of the turing apex probably isn't technical enough, but it should make some sense I hope.

Lastly I would like to say once again there is a reason why automotive engineers design cars and trucks with a wider front track width.

Steve

jeff024 · Post by **jeff024** » Thu Mar 23, 2006 12:59 pm

if this is the case why are the s-10s built by chevy the only ones doing this

2004 s-10 Track Front (in.)57.20
Track Rear (in.)55.10

2004 nissian frontier CC
Track Front (in.)60.00
Track Rear (in.)59.30

2004 toyota CC
Track Front (in.)57.50
Track Rear (in.)57.30

2004 Dakota CC

Track Front (in.)61.40
Track Rear (in.)62.40

killian96ss · Post by **killian96ss** » Thu Mar 23, 2006 3:56 pm

jeff024 wrote:if this is the case why are the s-10s built by chevy the only ones doing this

2004 s-10 Track Front (in.)57.20
Track Rear (in.)55.10

2004 nissian frontier CC
Track Front (in.)60.00
Track Rear (in.)59.30

2004 toyota CC
Track Front (in.)57.50
Track Rear (in.)57.30

2004 Dakota CC

Track Front (in.)61.40
Track Rear (in.)62.40

Chevy S10's are not the only vehicles designed this way. 3 of the vehicles you just listed have wider front tracks.

I never said all vehicles have a wider front track, but if you research enough of them you will find that most of them do have a wider front track.

Steve

jeff024 · Post by **jeff024** » Thu Mar 23, 2006 3:58 pm

I understand what your saying steve I just didnt want anyone mislead as to this is the way its gotta be the other 2 I posted above are so close Id just call them even

killian96ss · Post by **killian96ss** » Thu Mar 23, 2006 4:10 pm

I know I mentioned it above, but there is absolutely nothing wrong with having a wider rear track than the front. It is perfectly safe to do this and it seems like most people are running a wider rear track to compensate for the larger rear flares on the CC's. I was only trying to point out that this is not the optimal way to set up track widths. There are several cars out there that have a wider rear track like most Porches. They have different suspension set ups due to the rear mounted engines. I wish I could find a good diagram that better explains the turning apex I am referring to. It is very hard to explain, and I didn't do a very good job above trying to explain it.

Steve

jeff024 · Post by **jeff024** » Thu Mar 23, 2006 4:30 pm

2006 models full size trucks

ram 1500
Track Front (in.) 68.00
Track Rear (in.) 67.90

ford f-150
Track Front (in.) 67.00
Track Rear (in.) 67.00

Silverado 1500
Track Front (in.) 65.00
Track Rear (in.) 66.00

Honda Ridgeline RTS
Track Front (in.) 67.10
Track Rear (in.) 66.90

Nissian Titan
Track Front (in.) 67.50
Track Rear (in.) 67.50

Toyota Tundra
Track Front (in.) 65.90
Track Rear (in.) 67.30

Hummer H2
Track Front (in.) 69.40
Track Rear (in.) 69.40

Hummer H3
Track Front (in.) 65.00
Track Rear (in.) 65.50

Escalade ESV Platinum Edition
Track Front (in.) 65.70
Track Rear (in.) 66.70

Passat Wagon 3.6L 4Motion
Track Front (in.) 61.10
Track Rear (in.) 61.10

Viper SRT10 Coupe
Track Front (in.) 61.60
Track Rear (in.) 60.90

Bentley Continental Flying Spur Sedan
Track Front (in.) 63.90
Track Rear (in.) 63.30

Mustang GT Premium Convertible
Track Front (in.) 62.30
Track Rear (in.) 62.50

Infiniti QX56 AWD
Track Front (in.) 67.50
Track Rear (in.) 67.50

Jaguar X-TYPE 3.0
Track Front (in.) 59.90
Track Rear (in.) 60.50

Jeep Commander
Track Front (in.) 62.60
Track Rear (in.) 62.60

2006 Porsche 911
Track Front (in.) 58.60
Track Rear (in.) 60.90

2006 Maybach
Track Front (in.) 65.90
Track Rear (in.) 66.70

2006 Lamborghini Murcielago Roadster
Track Front (in.) 64.40
Track Rear (in.) 66.70

Range Rover Supercharged
Track Front (in.) 64.10
Track Rear (in.) 64.00

I would say from the info I have gathered here that there is no standard to what 1 can do as far as track ,seems like most are either even or wider in the rear

F9K9 · Post by **F9K9** » Thu Mar 23, 2006 4:32 pm

killian96ss wrote:I know I mentioned it above, but there is absolutely nothing wrong with having a wider rear track than the front. It is perfectly safe to do this and it seems like most people are running a wider rear track to compensate for the larger rear flares on the CC's. I was only trying to point out that this is not the optimal way to set up track widths. There are several cars out there that have a wider rear track like most Porches. They have different suspension set ups due to the rear mounted engines. I wish I could find a good diagram that better explains the turning apex I am referring to. It is very hard to explain, and I didn't do a very good job above trying to explain it.

Steve

The rear tire "scrubbing" you described, Steve, actually made sense to me. I find that a little frightening but, I actually understood

Post by **HenryJ** » Thu Mar 23, 2006 5:06 pm

Depending upon how you load your suspension, front to rear track width can change understeer and over steer conditions.
This may play a part in a circle track or Grand prix where wheels are purposely loaded and the balance remains the same. In a truck where the load varies trying to compensate is futile.
Scrubbing makes sense in a spooled axle. Not an open differential. A wider rear track will follow the front track closer in a turn, than a narrower rear track. Any farmer that cultivates will know that.
The wear difference may be there, but if I get 50,000 miles from a set of tires with a matching track and 50,010 miles with a narrower track. That would be inconclusive. I would have to see believable testing. Opinions are like A######s ...everyone has one. I'm not buying the reduced mileage bit though.
Maintaining proper air pressure and rotations will do far more for longevity that will ever be seen by having a wider track in the front.
There are a ton of "educated" people that believe some of the myths out there. Not all of it is untrue. However some of it does not translate to the real world.
Thanks for filling us in on this one. It was a new one I had not heard yet.

I've been waiting for someone to bring up that it is an old military specification

Steve2003 · Post by **Steve2003** » Thu Mar 23, 2006 5:09 pm

I was told that back in the day GM used the same axles for the front and the back and then you add the knuckles, it made the front wider, and thats how this all got started.

Post by **HenryJ** » Thu Mar 23, 2006 5:14 pm

Steve2003 wrote:I was told that back in the day GM used the same axles for the front and the back and then you add the knuckles, it made the front wider, and thats how this all got started.

Now something like that is more believeable

They do not put nearly as much though and research into these vehicles as we would like to believe. More often than not it is economics and convenience that shape the vehicle.

HEY!

I though I said I was going to leave this one alone! How did you guys drag me into this one? (I am weak...real weak

)

killian96ss · Post by **killian96ss** » Thu Mar 23, 2006 6:48 pm

Brule, thanks for giving your opinion on this subject!

I would be willing to bet that at least 80% of the vehicles on the road today have a wider front track, and it's not by mistake, especially since we are talking about several different manufacturers. Every vehicle I have owned has had a wider front track, which includes a couple of old RWD muscle cars, 2 FWD imports, and a couple of later model FWD & RWD domestics. All of them had a wider front track. There is a reason for this, however I am not doing a good job trying to explain why they are designed this way. I respect the opinions of the alignment techs that have explained this to me more than once which is the reason I posted the info. I think if I could accurately explain this design, you would then see that I am not just making this stuff up.

Oh well, if I can find some good diagrams I will definitely post them.

Steve

michaels86svo · Post by **michaels86svo** » Fri Mar 24, 2006 3:35 pm

Ok guys, I didn't know a simple question would turn into this.I thank you very much for your replys.A friend of mine just bought an S10 CC and has purchased the 1" spacers and 8" wheels with the same backspacing as mine.When he gets his installed I'll look at it in person and decide which to put on my truck.I think I'll probably end up with the 1.25".

jeff024 · Post by **jeff024** » Fri Mar 24, 2006 4:03 pm

with a 1.25 spacer on the rear mine line up great

killian96ss · Post by **killian96ss** » Fri Mar 24, 2006 4:58 pm

Here is a picture of my 1" spacer on the rear and a picture with the wheel on looking back.

Steve

michaels86svo · Post by **michaels86svo** » Sat Mar 25, 2006 5:18 am

Great guys.Thanks. By the way,nice looking trucks!

Steve2003 · Post by **Steve2003** » Sat Mar 25, 2006 11:41 am

michaels86svo wrote:Ok guys, I didn't know a simple question would turn into this.I thank you very much for your replys.

michaels86svo, you had a very good question, It stired up debate and that brings forth information which is a good thing. I learned alot of info from this post and I would like to think that's what this forum is all about

Post by **HenryJ** » Sat Mar 25, 2006 11:51 am

Steve2003 wrote:
michaels86svo wrote:Ok guys, I didn't know a simple question would turn into this....
...It stired up debate and that brings forth information which is a good thing. I learned alot of info from this post and I would like to think that's what this forum is all about

Absolutely!
Open wide the topic , bring in all views, sort out what you can use

04crewvt · Post by **04crewvt** » Sat Mar 25, 2006 12:23 pm

I went with Completvalues 2.5" Hubcentric in the rear and 1" hubcentric in the front, looks good on my rig.

F9K9 · Post by **F9K9** » Sat Mar 25, 2006 12:53 pm

It does look sweet~

ace · Post by **ace** » Wed Mar 29, 2006 11:45 am

If you have a ZR5 I would go with a 2" or 2.5" on the rear. I have 1.5" spacers and I don't think they are quite enough. The fender flares on the ZR5 push out the width a little so I would go with what I suggested if you have a ZR5.