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Mod | | | Forums66 Topics128,089 Posts1,056,145 Members48,436 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | I'm restoring a 55 1st series with NAPCO 4WD. That's not the point though...I've been working on these trucks for about 15 years, and prior to this one, worked on trucks with three speed trannies. Now,I'm workin on the old beast, which has a 4 on the floor. My problem is that no on seems to reproduce a floor mat that's anything close to original in appearance, or function! None of the mats i've see account for the transmission hump! They seems to be selling a 3 spd/Hydramatic mat as a universal fit. They don't fit the same way at all! The ribbing pattern is completely wriong as well...the heel area ribs are perpendicular to the ribs surrounding them...Has anyone found a source for an accurate 4 speed mat? I'm shocked and a little disappointed in all the reproducers out there that this wasn't addressed years ago. I swear, if I could get my hands on an NOS or good used mat, I'd start doing the repro myself! Hope you guys can help!! Thanks :confused:
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | who'd you get it from? have you checked the mats from "all" the suppliers? w/ the AD the 3 and 4spd should be the same but the shift hole isn't cut out - doesn't the 3spd have the same hump? - if you just ordered a mat for a 55 you may have gotten the TF [55-59] mat as many suppliers call 55 1st a 54
Bill | | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | The mats for 3 spd and 4 speed are definitely different. 4 spd tranny cover has a hump that surrounds the shifter hole that accounts for the tower on the SM420 transmission. I've looked at mats from most of the big suppliers, and they only list one mat. See, the hump isn't a smooth slope like the 55-59...it's a rectangular sort of extrusion/stamping that creates a ledge. The problem with using a three speed mat on a four speed tranny is in fit. The three speed mat drapes over a four speed hump, and with a little bit of time, feet pressing down on that area where there is a void will cause it to tear. My old floor mats were definitely rotten, but I wish I'd have kept the pieces, so I at least could show you what I mean.
Thanks,
Hook
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | oh, and I forgot to completely answer the other part of the question...3 speed tranny cover is completely flat, with a few horizontal stamps. Hydramatic tranny cover is essentially the same, excepting a hole where the transmission fluid dip stick fits. 4 speed has the hump.
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | i know whatcha mean - I've got both types of the TF series, just thought the AD only had a high rise one, but sounds like it's more like the 41-46 maybe your stuck w/ makin yer own!
hey people, hasn't anybody else here got an AD w/ 4 speed? what'd ya do?
Bill | | | | | Joined: Jun 2004 Posts: 336 Member | | Member Joined: Jun 2004 Posts: 336 | Bill: we plan to carpet the floor.
I hope to find a boot that will fit the shifter. Probably a long shot, so may end up making a sown leather job.
PS. I have an extra "flat" floor panel used on the 3 speed trucks. Free to anybody who can use it...
Gord 1954 1/2 ton 235 4 speed
| | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | Gord, I know most of the supply places do sell the boot for the 4 speed shifter...It's just that darn floor mat they haven't gotten right yet. You know what I'm talking about though, right? Didn't your old floor mat fit the transmission hump? I'm surprised more people aren't complaining about the lack of availability on these things. Thanks for your input, and good luck with your truck.
-Josh
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Jul 2000 Posts: 2,193 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,193 | Josh - the boots I have seen advertised have a round base. I would like one with a rectangular base that matches the hump. Have you seen one like that?
The truck didn't have a floor mat when we got it. A PO must have chucked it...
I understand where you are coming from - making a flat mat fit the hump contour would be a pain in the a$$. Heck - making a carpet fit without wrinkles will be a pain...
Gord 🇨🇦 ---- 1954 1/2 ton 235 4 speed | | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | I knew I wasn't crazy! I just found an old goldenstate pickup parts catalog from 92. They used to sell both 3spd and 4spd floor mats! So, I called them to see if they still do...Nope! For some reason, they stopped carrying 4 spd mats! Now, is it just me, or is that crazy? Their had to be just as many four speed trucks as their were three speed! :confused:
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Jul 2000 Posts: 2,193 Insomniac | | Insomniac Joined: Jul 2000 Posts: 2,193 | Old catalogue - good idea. I have a Pickups Northwest catalog hanging around and checked it; they list one. So, I checked online and guess what? Part no SD-2530 - $79.95 Pickups Northwest
Gord 🇨🇦 ---- 1954 1/2 ton 235 4 speed | | | | | Joined: Sep 2001 Posts: 168 'Bolter | | 'Bolter Joined: Sep 2001 Posts: 168 | Gord, Thanks for the lead on Pickups Northwest. Unfortunately, it looks like another dead end. The guy has only one of those mats left, and it's not correct. Apparently, it's got a "cross-hatch" pattern for the tread, and it's not got a molded in hump, it's just a little wider to account for the hump..and get this...he want's 137.95 for it...He said he'd send me a picture of it, but I'm pretty sure I'm not going to go for that. I'll keep searchin, and let you know what I find.
Josh
1956 GMC 100 NAPCO Deluxe 1955.1 Chevy 3600 NAPCO 1954 Chevy 3600 NAPCO
| | | | | Joined: Apr 2005 Posts: 196 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2005 Posts: 196 | > maybe your stuck w/ makin yer own!
Bill,
And how would one make their own? Mine (66 w/4-spd) is fair but getting rough.
I've considering ordering one from ChevyDuty but they seem expensive.
Rance
66 C10 FS/LB 292/4-spd manual (I also enjoy Hang Gliding) I'm too sexy for my hair, that's why it isn't there
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | Rance - one would go to a building supply or a carpet store and find some roll rubber matting of a width to reach from the seat to the dash-mat bottom, buy enuff to reach across the truck, and start nibbling away at it until it fits satisfactory here's what mine looks like - for the 4spd hump you just hafta cut a slit at the front of the hump and trim a bit off the top side of the slit so the piece above just lays under the part on the floor - make a paper pattern to start, and work from that - you can't hardly see it after awhile most of the matting comes w/ smaller ribs that go the other way [side to side on the roll, so front to back on the truck], but I found that heavier rib stuff that ran lengthwise and thought it was perfect - works until I get around to replacing the 4spd pan w/ a 3spd one! Bill | | |
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