When to replace seat foam?

[saxart]

I'm hoping you guys can help...

I'll be recovering the bench seat in my '70 long-bed as soon as the new seat cover shows up from Truckseats. I'm curious what the consensus is as far as when to replace the seat-foam when recovering these seats? For the most part, the foam in my bench seat is slightly yellowed, but doesn't seem to be missing any chunks or damaged in anyway. So, can I use this foam, or should I replace it?

As an aside, this truck is far from a full on resto, but rather more of a shop/patina truck that will only be driven occasionally. The biggest consideration is that I'm a bigger guy (6'2" #245) and really don't want a replacement seat foam that's going to put my head up near the inside roof, and my "chiseled 6-pack" abs against the steering wheel.

Any thoughts you have are greatly appreciated. In the meantime, here is a quick pic of what I'm working with. Obviously I'll have to patch in a small piece where the driver's right elbow would be. I haven't removed the cover from the seat base yet, but I'm guessing the foam isn't damaged since the cover is pretty much intact.

[tommys72]

I left mine just like yours when i recovered mine. Just got a little foam from an upholstery shop and added or built up where it needed it. Spray adhesive the new right to the old foam amd recovered it. Looks and rides great

[Grumpy old man]

Use it , foam discolors in less than a week when left exposed , yours is fine add a 1/2 " layer over the whole cushion top and bottom and then install your cover .been doing this for a living my whole life and then some .

[cypressbog]

I agree with Grumpy. I'd add a little extra toward the outside edges where you enter and exit because it looks a little more compacted there.

[Gromit]

It is hard to tell for sure from the single photo; but are you sure that is a OEM- type formed piece of foam and not just a flat slab?

Because my 1970 upper seat foam had radius corners whereas the one is your photo looks like it has sharp corners.

One comment I could make about old foam is it sometimes gets crumbly on the exterior even though the inside part of the foam if fine. But the crumbling makes it hard to keep the interior of the truck clean. I tried gluing nonwoven fiberglass landscape cloth on the bottom of my cushion and put some Mohawk matting on the seat frame and it helped improve that situation.

Photos attached

[saxart]

Wow, lots of good info here already. Thanks a lot guys!

Gromit-
Good point, and something I never noticed. Yes, this seat foam is a squarish shape when viewed from the front, where as it should be curved like you say. The previous owner mentioned that the seat was a replacement seat, but he couldn't remember what it came out of. I know the brackets are the later (71-72) style, so I assumed the seat was as well. I guess I'll know more once my seat cover shows up. (fingers crossed) If I have to trim the corners off, then so be it. Hopefully that's all it will need.

[Grumpy old man]

You won't have to cut the corners off you may need the extra padding on the aftermarket Taiwanese covers it that's what you bought. The cheapo covers sold online only have foam padding in the insert ( seat section you sit on ) not all the way across the faces as would be appropriate to upholster an almost 50 year old truck seat . You get what you pay for most aftermarket seat covers are junk .

[Gromit]

Here is a better photo of what I think is OEM original foam seatback from a 1970 C10 that you can use to compare.

In hindsight I am not so sure that I needed to go to so much trouble to duplicate the exact foam profile because the seat cover fits tightly enough and is so much stronger than the spring of the foam that maybe the foam would just squish itself to conform to the sewn contours of the cover if the shape was reasonably close.

In the photo I have not yet gotten to the step of shaping the repaired part of the foam but just roughly cut it out and glued it. As you know it is relatively easy to sand foam to shape with a surform tool with a 40 grit metal blade or other power tool.

[saxart]

Gromit-
I was thinking the foam may just "squish" down in the corners as you mentioned. If you look at the photo I posted earlier, it almost looks like you can see where the corners were squished. I figured I'd try it and see what happens. Worst case, it'll need to be trimmed.
Thanks for the pics, they all help tremendously!

Grumpy-
As mentioned, the seat-cover I ordered is from forum member "Truckseats". I think his stuff is made right here in the good 'ole USA.


I actually had ordered one of the cheapo online covers from a vendor who's name rhymes with "PEGS", but pulled the plug and cancelled the order after reading many sad stories of those seat covers here.

[Grumpy old man]

I'd love to see a picture of the inside of those covers , many replacement seat covers are built with just the seat insert sewn area having foam and just vinyl in the center and outside bolsters top and bottom .without the full foam construction (completely across the seat ) you can end up with a leaning towards the door feeling especially on an old truck seat .

[Gromit]

One other thing to consider about whether to replace old foam is the way it smells.

When I first got my truck the seat cover was worn through on the seat and I just thought the foam looked kind of grey. Eh what can you do..

But my girlfriend took one look and went "ewww gross"!

She wouldn't even ride in the truck until I redid the whole bench seat.

When I cut into the foam in the grey spot I saw she was right. (see photo attached) Only thing worse than previous owners grime is previous owners sweat from their nether regions (aka butt crack).

If you put the old seat foam inside an contractor size trash bag and out in the sun for a hour or so to duplicate the conditions of a hot truck interior and open the bag and take a whiff you will know right away..

Home depot has a sheet of foam big enough to replace your seat back for $25

Hope you guys had already had dinner...:-)

[saxart]

Gromit-
That's certainly an interesting (and gross!) photo. Who would think that some sort of a stain would leach down that deep into the foam? I have a tough time believing that it's "butt crack juice" (unless one of the POs drove naked!) but obviously some sort of YUCK got spilled or leaked there.

I may try your idea about putting the foam in a bag in the sun. My concern about this seat is a "mouse smell". I can't smell it now, but the bag-trick will certainly be more telling.

Again, the main reason I'm wanting to keep the original foam is that I just don't want an "overstuffed" seat that I've heard many of the new foam kits can give.

[tommys72]

i for one would never try the bag thing....why smell someone elses sweat? My foam didnt look like that anyway. Def was not grey when i got it apart

[sboris]

http://youtu.be/5rndD6tzZPo

Here's a little tip on restoring old foam to bring it back to life, steaming the foam, not sure what it would do to one with a lot of funk. This is what was done to mine, came out of a salvage truck that sat for 25 years. Turned out great. No foam added.. Hope this helps somebody

[Grumpy old man]

Steam works great for restoring foam back to shape also works great when installing covers to remove wrinkles , but don't use steam on your scrolled aftermarket seat the scroll imprint will disappear or become less defined .

[sboris]

^^ good to know

[saxart]

I was doing some thinking about this thread this weekend while out in the garage. "Hmmm... If the foam is incorrectly squared off at the top, wouldn't the frame be as well? I sure hope not!"

I think the answer is yes, and I'm going to have to source a new seat. I can't tell for sure, but it appears this seat is from a later (73-on) truck. Any thoughts anyone has is greatly appreciated!









I think if anybody could post some pics of a bare seat back frame from a known 67-72 seat, that would answer the question!

[Gromit]

Here ya go! (photo attached)..

Mine was a Fremont plant truck June 1970 build date C10 Custom. Pretty sure it was original..

[Gromit]

Here are two more photos to see if someone chimes in as to whether mine was original or not... I'm thinking lots of people on here can tell by one glance at the seat cover scroll or stitching etc.

I do think the fiberglass netting used as a foam reinforcement in your photo is likely later than 1970 because on mine GM still used regular old burlap.

Photos attached

[saxart]

Gromit-
I was hoping you would chime in. Grrr... Looks like I'm seat shopping.

Thanks so much. I really appreciate your help on this one!

[Gromit]

No problem.. I took lots of photos upon disassembly and it is amazing how one never knows what detail we will find ourselves looking for in those photos..(so take lots) - this is a good example and while I didn't have the entire upper seat frame I did have one showing the upper curve.

One thing that really surprised me is in your photo of your seatback is that you can see the imprint of the frame as well as the seat cover stitching in the actual foam. As if it was formed in place.

So in other words the photo seems to show evidence of the ways GM's seat manufacturing process changed from 1970 to whenever that seat was made.

It looks to me as if GM would put the covers on with that fiberglass netting in place and then blow the expandable polyurethane foam into the space under the cover? Otherwise how would the stitched imprint in both cover and steel frame be so pronounced?

Anyway it doesn't matter so much I guess but maybe you only need a seat back if you want to be 100% original to your 1970 - I'm thinking it less likely the seat rails and bottom changed unless the cab sheet metal dimensions changed too..

[saxart]

[QUOTE=Gromit;7641971] It looks to me as if GM would put the covers on with that fiberglass netting in place and then blow the expandable polyurethane foam into the space under the cover? [QUOTE]

Gromit-
Yes, it seems like that. If you notice, the foam on this seat sits much taller than the seat frame at the top. The foam has such a tight fit on the top most rail of the seat back, that it literally "snaps into place" when you get it in the right spot. There really wouldn't be another way to do that without somehow injecting the foam over the seat frame at the very least.

Sad thing is that just a couple weeks ago there was a pretty decent correct seat that just needed recovering right in the town I live!

Thanks again.

[Gromit]

I should say it is entirely possible that your seatback is still correct for 1970 - after all, I have evidence of only one example from one manufacturing plant at one point in time. Maybe GM changed over to the style shown in your photo in August 1970 for all I know or maybe at some USA manufacturing plants before others..

There are definitely people on here who know these kinds of details and maybe the challenge is more a matter of getting them interested enough to bother to comment.. because they can also just keep laughing as those of us (I mean me not you) who don't know while we learn and pay our dues.

[saxart]

Originally Posted by Gromit

I should say it is entirely possible that your seatback is still correct for 1970 - after all, I have evidence of only one example from one manufacturing plant at one point in time. Maybe GM changed over to the style shown in your photo in August 1970 for all I know or maybe at some USA manufacturing plants before others..

I dunno... Any of the seat covers I see for sale online very specifically show those "rounded" top corners on the seats for these trucks. If this seat was legit for this vintage truck, I would guess we would see more than one version of seat cover for sale as there is no way the same seat cover would fit both of our seats. I also would guess that the seats in these trucks were not made at specific truck assembly plants, but rather possibly sourced from one seat manufacturer and sent out to all the various assembly plants for installation. But, as you eluded to, it's all a GUESS by both of us.

Hopefully someone as helpful as you chimes in with even more assistance! (thanks again!)