CUTLASS 83-84 Hurst Olds Trunk Spoiler Rubber Plugs- Solved

69hurstolds

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I did a search on interwebz, came up with nothing. My original rubber trunk plugs are kinda hardened, and not as flexible as they once were. The rear plugs need to flex and partially fold to fit the hole. If you have an H/O, you know what I'm talking about. One of them is torn. So I kinda wanted to see if I could replace it. I honestly never looked at them much before as they just covered up the holes, but when I was in the trunk recently measuring the trunk torsion rods, I noticed the torn one again and that got me thinking about it.

Anyway, because there's nothing out there on the web that actually bothers to cover this, I decided to do my own research. It's a 1" hole plug, rubber, or epdm.

Here's the picture in the parts information. Note there is no part number listed. But a group number is for the plug. The issue is, the standard parts book has more than one entry for that group number. Imagine that.

1688585602465.png


Well, we already know it's a 1" hole needing plugged, so going with the 1", we get GM p/n 4410574. GM likes to use plastic ones too, but those won't conform to the tight turn of the rear holes.

Houston, you will have a problem using the GM part. Here's what a 4410574 looks like.

1688585966745.png


1688586007013.png


Will it work? Partly. The rear holes are further away from the mounting nuts, so any 1" plug that is flexible and fits will work. The front is where you will have an issue. Note the back of the plug is FLAT across. No indentation on the back side like the originals.

So I pulled the torn up one out and was inspecting it carefully and found some numbers molded inside. Turns out, this is a FORD PART!

Ford p/n 377678-S. Yep, that's it. 1" hole plug. The plug below is what the originals looked like, with the lettering inside the front side indention of the plug.

big_377678-S.jpg

The back side has an indentation in it which allows it to give some room to the front side stud when installed. It still is pressed into the plug a bit when installed, but it gives in the center to stay put anyway, so it works. Perfect? I didn't do it.
s-l400.jpg

The part has changed a bit over the years as far as where the part number is molded in, but the basic shape of the plug remains the same as does the part number itself. Comes in a pack of 8 if you get them from a Ford dealer. About $1.35 or so list price each. You may see FoMoCo in a little rectangle inside the indentation along with the part number, or the part number may be cast on the top outer rim of the plug. Again, the shape did not change.


s-l400.jpg


So there you go.
 
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Ribbedroof

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Jan 4, 2009
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Don't know about back then, but the S,N, and W part numbers are shared across the domestics on "standard hardware"
 

69hurstolds

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Don't know about back then, but the S,N, and W part numbers are shared across the domestics on "standard hardware"
I know what you mean, but I don't think this particular one applies. All the GM 1" rubber plugs I can scrounge up are different than these.

377678 doesn't appear anywhere I can find in GM's parts info. Ford is the only entity that seems to stock the part from way back when to now. About the only 377*** numbers that I can recall off hand were body bushings. Sh*t never makes any sense.
 
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84 W40

G-Body Guru
Dec 9, 2009
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I did a search on interwebz, came up with nothing. My original rubber trunk plugs are kinda hardened, and not as flexible as they once were. The rear plugs need to flex and partially fold to fit the hole. If you have an H/O, you know what I'm talking about. One of them is torn. So I kinda wanted to see if I could replace it. I honestly never looked at them much before as they just covered up the holes, but when I was in the trunk recently measuring the trunk torsion rods, I noticed the torn one again and that got me thinking about it.

Anyway, because there's nothing out there on the web that actually bothers to cover this, I decided to do my own research. It's a 1" hole plug, rubber, or epdm.

Here's the picture in the parts information. Note there is no part number listed. But a group number is for the plug. The issue is, the standard parts book has more than one entry for that group number. Imagine that.

View attachment 223892

Well, we already know it's a 1" hole needing plugged, so going with the 1", we get GM p/n 4410574. GM likes to use plastic ones too, but those won't conform to the tight turn of the rear holes.

Houston, you will have a problem using the GM part. Here's what a 4410574 looks like.

View attachment 223894

View attachment 223895

Will it work? Partly. The rear holes are further away from the mounting nuts, so any 1" plug that is flexible and fits will work. The front is where you will have an issue. Note the back of the plug is FLAT across. No indentation on the back side like the originals.

So I pulled the torn up one out and was inspecting it carefully and found some numbers molded inside. Turns out, this is a FORD PART!

Ford p/n 377678-S. Yep, that's it. 1" hole plug. The plug below is what the originals looked like, with the lettering inside the front side indention of the plug.

big_377678-S.jpg

The back side has an indentation in it which allows it to give some room to the front side stud when installed. It still is pressed into the plug a bit when installed, but it gives in the center to stay put anyway, so it works. Perfect? I didn't do it.
s-l400.jpg

The part has changed a bit over the years as far as where the part number is molded in, but the basic shape of the plug remains the same as does the part number itself. Comes in a pack of 8 if you get them from a Ford dealer. About $1.35 or so list price each. You may see FoMoCo in a little rectangle inside the indentation along with the part number, or the part number may be cast on the top outer rim of the plug. Again, the shape did not change.


s-l400.jpg


So there you go.
Nice detective work Mike, the only other Hurst/ Olds that used a Ford part was the 69 Hurst.
 

69hurstolds

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Jan 2, 2006
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Nice detective work Mike, the only other Hurst/ Olds that used a Ford part was the 69 Hurst.
I honestly believe it was the fact they probably had a grunch of those plugs from a Ford bin from somewhere already and said, "we'll just drill out a 1" hole and use these." There may have been a rhyme or reason with C&C, but then again, I've seen some crazy production decisions based on basically nothing.

The 69 H/O and 69 SC/Rambler got two Ford parts, actually. Sort of.

The first one is the custom air cleaner adapter which on top was tack welded a Ford ram air flapper with a ram air actuator from a mustang. Even has a "Ford" oval stamping and the production date on the end of the actuator. This flapper was also used on the 69 Hurst SC/Rambler, aka Rambler Scrambler, but was attached from underneath and mounted into the hood.

The outside mirrors were both passenger side mirrors stolen from the 68 XR7-G Cougar. The Cougars had such a large mirror pad mount, they had to use an adapter for the mirror base to make it larger. Additionally, it put the mirror out a bit so the wing vents for the Cougar could still operate. See below.

The non-remote passenger mirrors could be used on either side of the H/O because the bell was adjustable that way. The bigger problem is they're only for show because as outside mirrors on the 69 H/O, they suck donkey balls for functionality. But what's cool is the 68 Cougar driver mirror also had a remote adjuster similar to the stock 442 remote driver mirrors.

img_1184-jpg.41658



XR7-G adapter pad
1688670176170.png



XR7-G mirror (repro). Used original unit for sale at the same website for over $1,000.

1688670287741.png




Original used with adapter mounted-
1688670478530.png




Anyway, the mirrors weren't TECHNICALLY Ford parts. They were made by Raydot. They made the Cobra mirrors for Shelby, and also the XR7-G Cougar and were, for all intents and purposes, Ford parts. I remember talking to Doc Watson one time about it and someone mentioned Talbot mirrors and he vehemently said "They are NOT Talbot mirrors!" Rumor has it Talbot purchased Raydot about 20 years ago or so, as both are English mirror companies, but I have no confirming information on it either way. Last I knew, Aardvark International ownsed Talbot.

I recently bought a pair of NOS 69 H/O mirrors. Because they came available and were for a halfway decent price considering their scarcity. The guts are a tad different than the repops, and the bell is a bit thinner on the repops as well. I always find NOS H/O parts as good buys, regardless.
20230528_153739_resized_48dd52cb15d7fac636a8345204d32a18781e00b8.jpg
 
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Oct 14, 2008
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Melville,Saskatchewan
Don't forget the heavy duty "Dearborn" 3 spd manual Olds used till 70 when the Muncie version was finally made. Almost more Ford parts fit Olds than chebby parts.
 
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84 W40

G-Body Guru
Dec 9, 2009
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I honestly believe it was the fact they probably had a grunch of those plugs from a Ford bin from somewhere already and said, "we'll just drill out a 1" hole and use these." There may have been a rhyme or reason with C&C, but then again, I've seen some crazy production decisions based on basically nothing.

The 69 H/O and 69 SC/Rambler got two Ford parts, actually. Sort of.

The first one is the custom air cleaner adapter which on top was tack welded a Ford ram air flapper with a ram air actuator from a mustang. Even has a "Ford" oval stamping and the production date on the end of the actuator. This flapper was also used on the 69 Hurst SC/Rambler, aka Rambler Scrambler, but was attached from underneath and mounted into the hood.

The outside mirrors were both passenger side mirrors stolen from the 68 XR7-G Cougar. The Cougars had such a large mirror pad mount, they had to use an adapter for the mirror base to make it larger. Additionally, it put the mirror out a bit so the wing vents for the Cougar could still operate. See below.

The non-remote passenger mirrors could be used on either side of the H/O because the bell was adjustable that way. The bigger problem is they're only for show because as outside mirrors on the 69 H/O, they suck donkey balls for functionality. But what's cool is the 68 Cougar driver mirror also had a remote adjuster similar to the stock 442 remote driver mirrors.

img_1184-jpg.41658



XR7-G adapter pad
View attachment 223944


XR7-G mirror (repro). Used original unit for sale at the same website for over $1,000.

View attachment 223945



Original used with adapter mounted-
View attachment 223947



Anyway, the mirrors weren't TECHNICALLY Ford parts. They were made by Raydot. They made the Cobra mirrors for Shelby, and also the XR7-G Cougar and were, for all intents and purposes, Ford parts. I remember talking to Doc Watson one time about it and someone mentioned Talbot mirrors and he vehemently said "They are NOT Talbot mirrors!" Rumor has it Talbot purchased Raydot about 20 years ago or so, as both are English mirror companies, but I have no confirming information on it either way. Last I knew, Aardvark International ownsed Talbot.

I recently bought a pair of NOS 69 H/O mirrors. Because they came available and were for a halfway decent price considering their scarcity. The guts are a tad different than the repops, and the bell is a bit thinner on the repops as well. I always find NOS H/O parts as good buys, regardless.
20230528_153739_resized_48dd52cb15d7fac636a8345204d32a18781e00b8.jpg
Depending who you speak with those mirrors had different names English racing mirrors, Bullitt mirrors and torpedo mirrors. Back in the early 80s I was at a car show with my uncle and he pointed out the same mirrors, he did some racing with George Berejick back in the day thats how I got into oldsmobiles on a Triumph Spitfire. Can't remember what year it was but I think it was mid 60s.
 

84 W40

G-Body Guru
Dec 9, 2009
584
798
93
Don't forget the heavy duty "Dearborn" 3 spd manual Olds used till 70 when the Muncie version was finally made. Almost more Ford parts fit Olds than chebby parts.
You are correct but never was an option on a Hurst/Olds
 
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88hurstolds

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Jun 24, 2008
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I discovered years ago it was a Ford part and bought a ton of them for next to nothing from a Mustang parts supplier. They ran out... they are the correct ones with the inside PNs
 
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69hurstolds

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They're still next to nothing. Exactly what they're worth! :LOL:
 
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