What to use for bed seam sealant?

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pinballlarry1

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My '81 Fleetside long bed is missing most of the seam sealant and after searching the internet, I am wondering what everyone else uses. Generic polyurethane? 3M specialty, or what? Looking for the best for Montana winters. Thanks.
 

ali_c20

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Any quality automotive or marine sealant that has a high temperature range.
 

bucket

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Yeah, any automotive grade sealer. You will want something with a fairly heavy body and also something that cures semi-rigid.
 
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goldpack

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3m does have a question and answer line.

my 1986 has factory stuff that looks like grey caulk in a really thick bead inside the bed.
 

Jrgunn5150

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I use Evercoat brushable, I used to use SEM but I think they quit making it.
 

Scruffy49

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O’reilly carries a decent line of products, just left there pricing stuff for the lowrider build.
 

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