Dodge RAM 1500 wheel/tire size/weight debate

[oil pan 4]

There are plenty of instances where steel wheels can be lighter than alloy show off wheels.
Also if you get the light forged wheels and happen to slide into something immoveable the wheels tend to break, saving you from bending or breaking an axle.

[Superdutytd]

Smaller wheels will usually save fuel I've found on bigger trucks. My buddy went from 20" wheels to 17's on his diesel pickup and gained like 2mpg. Same size overall just the smaller and lighter wheels. Rotating mass is much more important than overall weight.

[t vago]

In order to provide some small amount of data for this debate, I have purchased a set of stock steel wheels for my Magnum. Today, I swapped out my stock alloy wheels with the steel wheels, and tomorrow I will top off the tire pressure and verify lug nut torque and do my daily commute thingy.

The steel rim weighs 23 lb 7 oz, and the alloy wheel weighs 22 lb 2 oz.

Stock alloy (10.035 kg):


Stock steel (10.660 kg):


On a side note, I got a really good deal. Normally, steel wheels go for about $60 per wheel in my neck of the woods. However, I found somebody who was willing to sell his wheels for $50 for the entire set.

[CapriRacer]

Don't forget that tires have a HUGE variation in rolling resistance. If you are going to do A-B-A testing, the tires have to be indentical for both sets - and that includes the amount of wear.

[t vago]

Originally Posted by CapriRacer

Don't forget that tires have a HUGE variation in rolling resistance. If you are going to do A-B-A testing, the tires have to be indentical for both sets - and that includes the amount of wear.

Well, the tires themselves are identical. They're the same tires. Only the wheels have changed. ("the wheels have been changed to protect the innocent...")

Now, I'm not quite sure the tires remained in their same positions when I had the wheels changed. That might affect the results, but very likely not in a statistically significant way.

[oil pan 4]

Were you considering doing warm air intake or more EGR or cooled EGR on your diesel?

[Miller88]

There are loads of dodge trucks with 5x5.5 alloys in junkyards up here. Fords too.

[ECONORAM]

Originally Posted by Miller88

There are loads of dodge trucks with 5x5.5 alloys in junkyards up here. Fords too.

I have considered that. I almost bought a set from the Classifieds on the DodgeTalk forum, but shipping was too expensive. They were OEM 17s and he weighed them at 28# each. Not as light as Centerlines, but certainly lighter than my 20s.

[edit] I've held off from pursuing 17" wheels because I am still looking to do a manual tranny swap. The factory 6-speed has a .78 top gear, and NV3500s (prior to the 6-sp) have a .73 top gear. The auto's top is .67, 4th is .75...and the truck doesn't do so great with the .75 on the highway. I've tried it a few times. I figure with 17" wheels the tires would be so short I'd regret it after the tranny swap. Typical size for my truck is 265/70R17, which is 31.6 inch diameter. My factory tires are 33 inch. With some math ratio MS Excel work, it looks like the 17s would make the engine turn another 100 rpms at 70 mph, with no other changes. But the .73 NV3500 5th adds another 170 rpm. Yuck.

All that said, I think she who must be obeyed is going to force my hand and make me buy new tires, and that means OEM size...

[SteveLNew]

Originally Posted by ECONORAM

So with 20s, the truck would lose 14# a wheel, or 64# total. With the 18s, the truck would lose 20# a wheel, or 80# total. The 18 inch tires are also about $30 cheaper each, and the wheels are $20 cheaper each.

Hmmmm
I can see how 20 X 4 = 80# total
but I do believe 14 X 4 = 56# total
Not 64# total?
Right?

I mean it seems like basic math.

[ECONORAM]

Steve, you are right. Now I'm even more disappointed. 16x4=64. Bummer. What's even better (or worse, depending on how you look at it) is the fact I discovered the OEM 20" wheels weigh 36# each if painted (like mine), 37# each if chrome plated. So, even less weight change per wheel. I still may go with some 17s like tvago if I can find a set for less than $110/wheel that don't look like ragged crash survivors...