Pick-up Truck: Topper/Cap v. Bed Trunk

GMC Full Size Sierra Pick-up truck. No need for hauling boats (I have a trailer), but wish to stow gear.

Regular windowed truck topper, we always called them a "cap" or, a hinged bed "lid" that makes the truck bed like a trunk.

Advantages, disadvantages, thinsg to look for in purchase? Thanks.

space and shape
I prefer a cap.

  • You can sleep in the back of a truck with a cap.
  • A cap lets you carry bikes and other ‘tall’ stuff in the back
  • Better aerodynamics

Out of site, out of mind is better
with the lid. More stuff can be stowed in the topper. As for aerodynamics, with toppers, it depends on which you get. The lids are probably a bit better for mileage, though they are quite heavy.


– Last Updated: Sep-21-07 2:10 PM EST –

I've had toppers on all my trucks, dating back 22 years. Two years ago I had to do without one for 4 months while waiting for a topper to be made for a new truck model. It was not a happy time. I really missed having the following:

1. Locking low-maintenance "room" for bulky or wet gear.
2. Roomy, safe, quiet sleeping area (I hate tenting on road trips).
3. Nice place for the dogs and crates to ride: secure, no dog hair on seats or carpet, well-ventilated with 3 windows to choose from.
4. The topper itself can take a set of rack tracks that allows you to adjust crossbar spans (if you decide to add a roof rack). I can get about a 5' span on the top of my topper for a 6' cargo bed.

Gas mileage has never gone down a whit due to having a topper on the truck. In fact, I've seen claims that a topper can improve mpg--however, my experience is that it doesn't change the mpg either way. Probably depends a little on the design of the topper.

I love the fact that neither the topper nor the kayak trailer hurts mileage!!!!!! Yet I can carry a lot of gear and sleep comfortably and quietly.

As far as security goes, "out of sight is out of mind." If you are putting things like bikes in the back, cover them up (or better yet, install window curtains) so as not to attract thieves. I have some opaque coated-nylon "curtains" for my topper, and I always have a large tarp inside for various purposes.

Only downside is higher cost (than a lid). If you need to carry really tall stuff that's higher than a topper roof, that would be another downside...but then a lid wouldn't work, either. You could get a rollback type of cover for that application.

I have a cap on my Tacoma primarily so that I can sleep in the back of the vehicle. I agree with most of what others have said with a few additions.

If you ever do decide to car top boats or gear, it is fairly easy to install “gutter brackets” to the top of the cap that will accept the good, old Quick and Easy brackets.

Bed caps significantly limit rear visiblility. The rear window on the cap gets dirty quickly, and even when it is clean, when you look back out the cap, you are looking through 3 layers of glass: 1. back window of cab 2. front window of cap 3. back window of cap. It is hard to clean the back window of your cab and the front window of your cap, with the cap in place. If you get a cap, “Texas Mirrors” fitted to your truck to minimize the rearward blind spot.

A cap will limit the height of anything you haul in your bed. Obviously, so will a tonneau cover, but I would guess these are easier to remove temporarily than a cap.

I have owned Leer caps and have had good luck with them.


– Last Updated: Sep-21-07 4:02 PM EST –

Again I agree with all said above and I too sleep in my truck bed with the cap. However, I have a Leer topper that has a removable front window to make cleaning both the topper window and the truck rear window a breeze. Plus by putting in a screen with velcro I get great ventilation through the topper when I open the side sliding windows and the front window is out with a screen in place.

Mileage does not suffer with a cab high topper. It might if you got a topper that extends above the height of your truck cab.

Also you can mount Yakima landing pads directly on the topper if you want a rack system with maximum spread that is not adjustable. Cheaper than the adjustable rail racks.

I would be lost without
the cap on my pick up.

When we head to Florida each winter pulling a travel trailer behind it, we carry two mountain bikes, back packing gear, canoe paddles, kayak paddles and then a half dozen of those big rubber maid tubs with the lids which have all the biking gear, paddling gear, etc in them.

I have had a cap on my last four trucks.

I have the fiberglass one and they will match the color to your truck.

If you should ever want to carry boats on it, you can get the Yakama “landing Pads” which bolt right through the top of the cap.



I have both
cap and cover (lid) on a full size chevy and on an s10 I wish I would have 2 caps.With the s10 I can only load as high as the bed is.The only disadvantage with a cap is if your used to turning around and looking over your right shoulder you better have good windows in the cap,not those bubble windows like on my 1990 leer chalanger aluminum cap.

Another vote for cap
Height (inside) wouldn’t be as much of an issue on a full size pick-up. I have had both the cab height and the extended height on my Rangers and prefer the extended top. I would certainly choose a cap over a cover and so would my dogs.

Cap/Shell and Carpet Kit
I have a 2002 Tundra and have always had a shell on it as I did with my '85 Toy.

I have also had raised carpet kits so sleaping is quite comfy. They allow storage under and in side pods and additional privacy inside, did I mention that they are comfy. It is nice to camp with an actual bed with foam padding and that are dry and quiet with built in lighting and curtains. It’s like a small camper without the gas consumption.

I have Yakima racks with Shark cradles on the front and Hully Rollers on the back and I use the false gutters on the side of the cab and take the racks off between use.

Have a cap…

– Last Updated: Sep-21-07 7:29 PM EST –

Have a cap on my pickup; a 4x4, 2006 Ford Ranger.
Wife has a cap on her pickup; a 4x4 2004 Ford Ranger.
Previous truck, a 2001 Toyota Tacoma had the same rig.
Both caps match the color of the truck.
Both caps made by a company called Jason; have owned 3 of them & never had one problem with any of them. They're fiberglass.
Use Yakima racks on cabs of both trucks, and Quick & Easy towers, on fake rain gutters on both caps; never had a problem with that setup.

If there is a downside to a cap, I don't know what it is? Keeps gear dry(they don't leak) & secure from an honest person. Dry, protected sleep area if so desired. One truck will haul all the gear we could ever possibly want for on a multi-day outing. We're both so used to driving with the caps on that visibility is a non issue. Both trucks have good sized mirrors. Both caps are held onto truck with 4 adjustable clamps & could be removed in about 20 minutes if necessary. I personally would not want a pickup without a cap. If figured on the basis of cost per year that we keep our trucks, I'd guesstimate the yearly cost of the camper to be about $125.00 per year. Worth every penny to me.
Initial cost of trucks is dramatically reduced; due to father-in-law being retired Ford employee.


raised carpet kits
What type of bed platform do you have, homemade or store-bought?

carpet kit
My carpet kits have been all been store bought.

They are not all that hard to make but my lazy bone kicked in and the ones that I have had were pretty well designed and I didn’t have to make any mistakes.

My current one happens to match the dark gray shell liner material which also matches with the interior of the cab.

It has two large and two small pod sections on each side with a center section that can drop down to truck bed level for higher items or the center or the whole thing can come out easily. A total removal takes about 10 minutes with no tools.

I added a 1/8" deck board below the center area so that I can put things down there without damaging them or the bed and I also made a removable wall that prevents items like grocerys from sliding forward under braking.

Very versatile.


Thanks for the replies.

– Last Updated: Sep-22-07 8:35 AM EST –

I will get a topper/cap. I would indeed like top put my bike in there once in a while, and toppers seem better for that and other high things. In fact, if I had the hard tornneau only, and had to put something big in there when I am at the mall 30 miles away, what do I do; drive home with the tornneau open? Cannot see that happening.

So, thanks for the tips. I had heard, in fact, about the bear of seeing through and cleaning he window-window interface between the cab and the cap when it gets durty and hard to clean, but if the front cap window is removeable, that would help. That's be a good thing to look for when I buy.

Anyone have ideas abut gear storage within the cap? PFD, paddles, hatch covers, et cetera. Rather not have them slamming around.

I don't know what the carpet riser is that you all speak of, but would love to see a link or photo.

One tip, another person gave me, for gear storage that some of you might not have thought about is hammocks. They bought some small hammocks--I think Wal-mart and other places sell them specifically for storage, like putting in the corner of a kid's room or using for sprts balls--and stringing up the long way inside the cap. Sort of like a sling, and throw stuff in there... allows things to dry out (esp is cap windows openw hile you drive), and keeps things neatly off the truck bed. Just a thought.

Anyone have others?

Tip #2

– Last Updated: Sep-22-07 10:20 AM EST –

I have some tiedown points in my Dodge Ram bed which I leave small nylon lines about ten foot long on for tying loose items to. This way I can retrieve my loose items easily without climbing into the back of the bed.

I have also cut a pvc pipe to go across the topper from side to side where it sits on the truck bed held in place with a couple of c-clamps. This lets me hang wet items on hangers or just laying gear across the pipe. When not in use I just move it out of the way against the back of the topper.

Tip No. 3

– Last Updated: Sep-22-07 4:09 PM EST –

Keep a whole bunch of various length bungees in there at all times.
You can hook them to the cap hold down clamps, the bed of the truck drain holes or the couple of hooks that come with the truck.
They come in handy for securing the bikes and all the other stuff where you want them.

You also can by an expandable heavy duty rod that has pads on both ends and can tighten up against both sides of the truck either in front of or behind a load to keep it from shifting during travel.


I have cabinets that I made
I have a Dodge Dakota. I made two cabinets each about 14" wide, the length of the bed and bed rail high. One cabinet fits down each side over the wheel wells. this leaves about 32 " down the center where i can sleep. In them I keep PFDs, shoes, anchors, fishing gear, some camp gear (stove, cook kit). On top of each cabinet I have homemade racks. One side holds 4 two piece fishing rods and the other side holds 3 canoe paddles. The paddles fit into slots and are held with bungees. Same with the fishing rods. I don’t have pictures right now but if I get some I will post them.

Keeps all my gear handy but out of the way and not just laying around.

against toppers
I am probably the only one who doesn’t like shells or toppers. I have one on my nissan for 15 years and hated moving it gack to wash the rear windows. Had to do this about every 3 months, plus if I wanted to carry an oversize object it took 2 to take it off.

My Tacoma does not have one and I love the open bed. Opening the rear sliding window gives great airflow through the cab and putting dirty, heavy and oversized things in and out are a breeze.

bungees, ropes etc.
Having a cap (at least a fiberglass one) means the ride will be a bit softer and things will bounce around a little less. A cap helps most with a stiff suspension, tow package etc. My Silverado is probably the same as your Sierra & I use the 4 corner hooks all the time + the 2x4 slots in the bed. I’ve had aluminum, fiberglass, flush and hi-top caps on a variety of trucks & my next one will be a fg cab-height. Biggest problem for me is that some have tinted glass side windows that seem worse when viewed with polarized sunglasses.

If you don’t care about matching the truck color, used caps are a bargain - but its not always easy to find a color match. I know people like to take them off before trading in a truck and others who don’t want the one on a used truck they’ve bought.

If you get a cap
Get one with side windows that open. It never fails that no matter what you want it can not be reached from the tail gate and the older you get the harder it is to crawl to the back of the bed (truck that is).