The Stovebolt Site Forums The Shop Area Interiors Unison seats finally installed

I finally got this project done with the exception of a couple of little cleanup details. I had had an old scab set in storage for years and had seen 1 set in person but never had the opportunity to sit in any. This is pretty much a 54 and 55 1st series only item and I think Chevy only. Just had to share my proud moment. Thanks, G.H.

unison seat installion album

What does it feel like, Greg?

Happy New Year,

Believe it or not, by the time I was done installing them, I was too dirty and too tired to sit in them. I am anxious to take them for a drive. I just covered them up with a blanket and locked the doors.

I'm jealous.

Happy New Year

Pictures?

John,

Greg added a picture link in his first post, late last year.

Greg,

I'll look again, but, did you take photos of the "floating" driver's seat's mechanism?

Sorry Tim, I should have snapped a picture when I had the driver's seat assembled but out of the truck. It was such a mad scramble yesterday getting them completed that I neglected the pictures until the project was done. I had the assembly manual, your pictures, and a picture that is a factory drawing out for consultation when putting it all together. I looked at the assembly manual and made a list of all of the hardware trying to get an idea of what all fasteners were the same by comparing the listed part numbers. Then I tried to take that list to the master parts guide to get details but the numbers did not show up. I had to "wing it". It involved going to the hardware store to get different lengths of all bolts until I determined exactly what the perfect bolt would be.

Let me try and explain the "unison" part. Think of the lower seat cushion as 3 parts. The bottom frame which sits on the seat pan and is mounted securely, the upper frame which is the plane that you sit on, and both are separated by "suspension coil springs". Reasoning all of this out, in a normal seat, the seat back is also mounted solid to the seat frame so that when the seat bottom compresses, your back actually slides up and down across the seat back. In this unison seat, the seat back actually bolts to a hinge plate that mounts to the upper plane of the seat bottom cushion. The upper part of the back cushion has those pivot bars that allow it to travel up and down within the seat frame letting the back cushion travel with your back when the lower cushion compresses preventing that "rub". Then there is the (as the upholstery guy put it) an "overly engineered" flapper valve in the bottom of the driver's seat lower cushion to "control rebound". A pretty slick system when you reason it out.

On my seats, someone had welded up the hinge plate and it was at an odd angle and trying to poke through the back of the seat cover. I think someone was trying to weld a split in the spring frame. I had to take a cutting wheel on a dremel and cut that weld loose to get the correct movement. The suspension bars have the bushings going into the bar in opposite directions on both end of the bar. They actually hook to the metal seat back and then to the seat frame. I used washers at every "rub point to try and increase the ability to move without wear points". The assembly manual shows some "optional" spacers but I have not seen them on any of the seat sets that I have pictures of. I just kept looking at pictures, bolting up everything, and measuring the width to make sure everything would come out correct. It was an exercise in trial and reasoning. There are fasteners that are supposed to be phillips head where currently I am using hex head but I will change the ones that will make a visual difference in due time. Like I said, I am anxious to go for a test run but want to do some tune up work before I drive the truck very far. This looks like it is going to be a neat trick though. Walter said they are the most comfortable seats he has ever sat in and invites people at shows to sit in them to prove that point.

I will send you a drawing that I found and used as a reference source.

Greg, Those seats look great. I never knew what they were called. Where can I find more information on the Unison seats? About a year ago my brother and I were scavenging through a yard that was closed and scheduled to have everything scrapped and came a cross a 54 dump that had those seats. We didn't know they were rare but just thought they would look good in his 54 4400 Dump. We took them out and paid the scrap man $20.00 for anything we could carry out that day. Looks like we got a good deal. He's getting ready to take to the upholstery shop so we may be bothering you for tips and pictures. Once agin they look great. Brian M

I understand that they were found more in larger trucks. It is amazing how many people have not heard of or seen them. I hope you got all of the pieces to install them.

I saw a set in a 55 1st series truck sometime in the 80s. I talked with the truck's owner about them and years later, bought an extra set from him that he had picked up.They had been in storage waiting for me to get to that part of the project. I ran across another truck owner and member of this site that was mostly done with a beautiful 55 1st series truck. He was determined to install all possible options but had not heard of the seats. After searching for a set for him to restore and coming up empty, I offered the set that I had with the understanding that he would replace them to me in due time in similar condition to what I sent him. This bought some searching time as I am not setting any land speed records getting my truck done. He sent me pictures after he had restored the truck with the seats and they looked amazing. I helped to try and locate a replacement set. It seemed to be pretty hit and miss. Then 2 big boxes showed up and when I opened them, they contained the seats you see in my pictures. He had decides to reward my "leap of faith in sending them to a complete stranger" along with a very nice letter of which I am equally proud of.

When you get ready to install your seats in your truck, check out the other albums in my webshots and feel free to ask questions.

The [i]Ride-Control[/i] (Unison) seat was available in 1954-55 as standard equipment on Chevrolet COE trucks, and was available as an option (RPO 264) on many other 1954/55 Chevrolet trucks.

Greg, Walter, and I might be stretching the types of options the seat might have been available with.

In all of the pictures that I have been staring at recently, and they are quite a few, It looks to me like the COE seats use different "stands" on the driver's seat that go from the cab floor up to the slider assembly that the seat pan mounts to. I don't think it would be any huge hurdle but it might be something to keep an eye out for when gathering parts. by the way, big_dan_1950 on this site was reproducing those mounts as well as some other metal items for these seats. here is a link to some of his work. http://s257.photobucket.com/albums/hh220/dans1950/54%20truck/?action=view&current=DSC02129.jpg

I have that style of seat in my '54 half ton and thought it was really neat that that passenger side cushion lifts off to reveal a nice area to stow tools and roadside equipment. Did not realize that they were that rare. It is a very comfortable seat

Where were all of these people that have these seats that didn't realize they were anything special when I was trying to locate a set? I think you guys are just messing with my head now!

Anyway, they are pretty rare but as soon as you get a set for yourself, like everything else, they start coming out of the woodwork. I am looking forward to a nice long drive to try them out but it may be springtime before the real test is done.

Nice seats Greg...

I noticed these Holes 1 & Holes 2 on my 54... Are they for the Unison Seats set up ?

[This comment was added later - the holes in the photos might not be for the Unison (Ride-Control) seat holes - The Factory Assembly Manual has good illustrations. Read information in later posts.]
The holes in photos 35-36 are for the Unison (Ride-Control) set-up.
I cannot see enough of photo 37 to figure that one out.
Photo 24 is another place the Unison (Ride-Control) seat set-up attaches to (I think) - 2 bolt holes for one of the rear-cab wall-brackets (I think).

[This comment was added later - the next sentence is incorrect. Read information in later posts]
Nothing has to be drilled in the 54/55 cab in order to install the various parts of the Unison (Ride-Control) seat assembly.

The holes in the front skirt are for the unison seats but I disagree with Tim on the hole drilling. There are indentions to mare the locations where 4 holes need to be drilled in the floor pan for the back of the brackets to bolt down and then 4 small holes to mount the side trim plate

on the driver seat the wood that is under the bottom springs what is the metal flaps for ? what are they suppose to do ?

The metal flap is simply an air valve to "help control rebound". The upholstery guy pointed out that the same thing could have been accomplished by drilling holes and called it "over-engineered".

Greg is correct (I have edited my post above).

After a communication with Greg, I quickly realized that my recollection of the "dry fit" of the parts was not correct. I went out to again dry fit my seats, and then I looked in the Factory Assembly Manual (of course, I should have done this before I posted above).

The holes for the two brackets on the rear wall of the cab are there.

The eight holes on the top lip of base (seat riser) under the passengers seat are there (two holes on the front and two holes on the rear for the two bracket-and-channel to seat-riser pieces).

The four holes in the front side of the base are there for the driver's seat support bracket (two for each front support bracket to seat riser).

The 4 holes in the floor at the rear of the driver's seat front support brackets are not there (two bolts through the floor at the rear of each of the two front seat supports). As described in the Factory Assembly Manual, there are 4 very obvious dimples in the floor - drill four 3/8" holes.

The holes for the cover panel are not there (sheet metal cover for the exposed top of the floor-base to the left of the driver). After installing the seat, locate the cover panel and drill the holes in the top lip of the floor base. I think that my cover has an extra "previous user supplied?" hole in it. My guess is that there is a hole near the front left edge, a hole about 1/3 back on the front left edge, and two holes at the rear.

If you have the 1947-1955 Factory Assembly Manual, look at SECT. 0, SHEET 4.01 and SECT. 1, SHEETS 2.06 through 2.12