The Stovebolt Site Forums The Shop Area General Truck Talk Long Bed Step Side to Fleetside

I have a ‘57 3200 that has the 89” long bed step side. I’m getting a 98” fleetside bed off of a ‘58 3600. What all do I need to make the swap work? I’m assuming the mounting is pretty close, but what makes up the 9” of difference?

I'm not aware of any 89" bed on Task Force pickups...are you sure you measured that right?

The '57 3200 step side is a 1/2 ton long bed and '58 3600 Fleetside is a 3/4 ton long bed and both have 98" beds.

Mike B

Edit...I found the 1955-56 3200/3600 had the 89" bed and 57-up 3200/3600 had the 98" bed.

‘55.2-very early ‘57 3200/3600s have 89” beds. The GM info packets lists the 89” bed for 55.2-56, and 98” for ‘57-‘59. I’m pretty sure they used stock on hand of 89” beds in early ‘57.

I’ve measured my step side and its 89”. I’m wondering what’s different about mounting the longer bed since the wheelbase didn’t change and GM says the frame is the same length ‘55.2-‘57.

Thanks,

Danny

Somebody transposed #s. 89” for both? Maybe?

I can’t get this to work on my phone, but these are both ‘57 3200s. The extra 9” is all behind the rear fenders.

89” bed
[img]https://img123.s3.amazonaws.com/2018/12/08/89/20d3860e6bb224ba_229f8c92e369c6.jpg[/img]

98” bed
[img]https://cdn1.mecum.com/auctions/da0914/da0914-196103/images/da0914-196103_2.jpg?1409875328000[/img]

I don't have one to look at but you will need some sort of bed extension with at least one cross brace to support the end of the bed.
There may also be some differences in the spare tire mounting. GM most likely made up a new frame as the 89" bed was no longer used after 57.
Fred

The 1957 Chevrolet Truck Engineering Features book talks about the "new" 98" pickup box for the 3204 and 3604 models. If the assumption is Chevrolet used the 89" box on early 1957 models (to use up inventory) than they would have needed to use the 1956 frame as well (which is 8" shorter than the '57 frame).

Just curious, what year is stamped on your 1957 short frame as part of the serial number? It's found on the top of the frame above the front axle, drivers side.

So to answer your original question, you will need to add frame extensions to the short frame in order to bolt the rear bumper on and transfer any bed mount holes for the longer bed to the shorter frame.

Mike B