Headlights and spoiler

[sewlow]

What I called a spoiler is also called a valance or an air dam. I thought I should clear that up. A company named LKQ carries them and they show 2 of them for our trucks. One is $13 and the other is $24. I have bought from them before and the quality is really pretty good. I forgot all about them till yesterday.

The aftermarket valances are more brittle than OEM, especially apparent at the mounting holes.
The OEM ones are made with a much more flexible plastic.
Went to a job site with my '98. Customer says to park on the grass in his backyard. At the end of the day when I went to leave, found the truck had sunk down past the lower lip of the wheels. Really stuck. Couldn't drive it out. Crawled under & hooked a strap to the front frame rails & pulled it out with a tractor.
When it was being pulled, that factory front valance was squished right up to the bottom of the bumper by the tow strap. Mashed right outa shape. My customer was worried that it was being trashed beyond repair.
Once the truck was freed & back on pavement, that OEM valance just popped back to it's original shape. Not one mounting point broken. Couldn't tell it'd been twisted around like a noodle. We were amazed. Especially when that valance was the 12 year old original.
On my '97, I installed an aftermarket valance with fogs.
That thing didn't last 3 years. In that time I had it off 4 or 5 times just to jury-rig it back on.
Just touch one of those cement block things in a parking lot. Center of the valance or just a corner. Didn't matter. Sure as sh*t, one or 2 of the mounting bolts would pull through & snap the plastic mount.
Or...
The actual valance would crack, split or chip where it touched anything.
Got to the point it couldn't be repaired. Went back to the non-fog flexi factory one.

 

[94K3500PROJECT]

Confused as to having a spoiler on a pickup. Just for cosmetics?

the front air dam will help with aerodynamics and increase MPG.
At least on the gmt800 trucks....no reason why these are different.

 

[thegawd]

heres a couple pics of the spyder glass lenses. also I've considered removing the lower valance. Iv busted one of the mounting holes with a snow drift while having some fun. I could simply put it back on with a large washer but havent bothered yet. this truck is more of long term hot rod like project but a farm truck always. it hasn't been on the road since I brought it home but iv managed to put 250kms on it hauling firewood and teaching my kids how to drive and do donuts in the fields.

but I know that the gm engineers put this truck (gmt400) in a wind tunnel and made them aerodynamic. what exactly does the lower valance accomplish? I thought it might have cooling properties but I don't know. this truck is definitely heading back to the street next summer hopefully and if this helps mpg I want to keep it.

Al

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[drewcrew]

heres a couple pics of the spyder glass lenses. also I've considered removing the lower valance. Iv busted one of the mounting holes with a snow drift while having some fun. I could simply put it back on with a large washer but havent bothered yet. this truck is more of long term hot rod like project but a farm truck always. it hasn't been on the road since I brought it home but iv managed to put 250kms on it hauling firewood and teaching my kids how to drive and do donuts in the fields.

but I know that the gm engineers put this truck (gmt400) in a wind tunnel and made them aerodynamic. what exactly does the lower valance accomplish? I thought it might have cooling properties but I don't know. this truck is definitely heading back to the street next summer hopefully and if this helps mpg I want to keep it.

Al

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I read on here somewhere that aftermarket headlight housings don't diffuse the light as good as stock housings. I think it said it was worse the farther out the light went. I don't know for sure just repeating what I read.

 

[thegawd]

your probably right but that is not the case with the spyders. they are as much an upgrade as doing the 4 high mod in my opinion. I run cheap stock bulbs but have the 4 high and low beam mods, my lights are bright, way brighter than the stock configurations. they are aimed perfectly and I never get flashed. they are also dot approved. it just sucks that they have those minor flaws. I thought it was a one off until I bought the second set.

I believe that the spyders are a huge upgrade that also look oem.

Al

 

[thegawd]

heres something to read about truck aerodynamics from GM. I think I will keep it. it does direct air underneath away from the suspension and cavities as well as up and into the rad for more efficient cooling. heres some info from gms engineers and I'm pretty sure that the gmt400 was the first truck in a wind tunnel.

Al

https://media.gmc.com/media/us/en/g...news/us/en/2013/May/0516-gmc-pickup-aero.html

 

[94K3500PROJECT]

heres something to read about truck aerodynamics from GM. I think I will keep it. it does direct air underneath away from the suspension and cavities as well as up and into the rad for more efficient cooling. heres some info from gms engineers and I'm pretty sure that the gmt400 was the first truck in a wind tunnel.

Al

https://media.gmc.com/media/us/en/g...news/us/en/2013/May/0516-gmc-pickup-aero.html

The LLY Duramax guys would add a front air dam from a 1500 and gain 1mpg.

I think the aero/fuel mileage is why front bumpers are SO tall now

 

[PlayingWithTBI]

heres something to read about truck aerodynamics from GM.

That's interesting about tail gate up/down and a net instead. I remember seeing something about the valance helping with cooling and MPGs but, don't recall where.

 

[thegawd]

I started a new discussion on this topic so I done hijack this thread.

Al

https://www.gmt400.com/threads/truck-aerodynamics.51418/#post-1136202

 

[Sam Cooper]

The aftermarket valances are more brittle than OEM, especially apparent at the mounting holes.
The OEM ones are made with a much more flexible plastic.
Went to a job site with my '98. Customer says to park on the grass in his backyard. At the end of the day when I went to leave, found the truck had sunk down past the lower lip of the wheels. Really stuck. Couldn't drive it out. Crawled under & hooked a strap to the front frame rails & pulled it out with a tractor.
When it was being pulled, that factory front valance was squished right up to the bottom of the bumper by the tow strap. Mashed right outa shape. My customer was worried that it was being trashed beyond repair.
Once the truck was freed & back on pavement, that OEM valance just popped back to it's original shape. Not one mounting point broken. Couldn't tell it'd been twisted around like a noodle. We were amazed. Especially when that valance was the 12 year old original.
On my '97, I installed an aftermarket valance with fogs.
That thing didn't last 3 years. In that time I had it off 4 or 5 times just to jury-rig it back on.
Just touch one of those cement block things in a parking lot. Center of the valance or just a corner. Didn't matter. Sure as sh*t, one or 2 of the mounting bolts would pull through & snap the plastic mount.
Or...
The actual valance would crack, split or chip where it touched anything.
Got to the point it couldn't be repaired. Went back to the non-fog flexi factory one.

The factory spoilers and air-dams you refer to are made of ABS plastic which is quite pliable and less prone to tearing than the typical after-market fiberglass pieces. FYI LKQ is an automotive salvage company, who owns the Pick and Pull chain. They are owned by Schnitzer Steel Company. When the vehicles have been picked over for parts the remnant is crushed and shredded into small metal bits which they ship to China.