This is something I wanted for a long time, the one model you could not buy, the extended cab long bed gen 1 Dakota.

Just wondering if someone else has done this, with prices of these so reasonable surely it wouldn't be that big of a deal to undertake this, extend the frame 12" and reinforce, add same to driveshaft, extend rear harness wiring and brake lines plus insert a chunk of exhaust pipe.

Anyone else thought about this?

Steve

 

I have wondered the same thing. I would think, if you start with a extended cab truck, remove bed, and cut frame behind the cab. Find a donor long bed truck, cut frame and attach to extended truck. By doing it this way, you would have all the mounts in place.
Also, I wonder if you may need a 2 piece driveshaft....
But at any rate, it would be a neat project.

 

There is one problem.

For 1988, my long wheel base 8' bed standard cab Dakota has the unenviable record of the largest 2WD turning radius; larger than a lot of 4WD trucks that year.

I think an extended cab 8' bed Dakota would end up with a turning radius that would make the captain of the Queen Elizabeth point and laugh ...

RwP

 

Your plan is a good one but after I pondered this problem for a while it occurred to me that you would have a better match if you spliced the frame not directly at the cab / box junction but perhaps back further. That way the junction isn't directly visible where the two pieces meet. Also I would think that an overlapping splice with reinforcements would help make the extra 12" frame length a non-issue. I'd personally like to take a look at where the bed mounts and see if it's the same between the two beds near the cab, if that were the case you could leave the forward bed mount and splice the two frames together behind that. Which ever way a person goes there are several options out there.

BTW, the ext cab trucks already have the two piece driveshaft.

Ralph
You may be correct about that, I hadn't considered the turning radius but it might be an issue. You would end up with one long truck that's for sure, but they did this with the full sized Rams too so it wouldn't be that weird, it would just look unusual. I'm wondering if the turning radius for the later gen 1 trucks got any better? After they switched to the different front end setup maybe it improved a bit. Then again it could be a function of the rack & pinion steering, who knows. At any rate adding 12" isn't going to do much harm since the problem already exists, it's just something that needs to be managed.

If I do undertake to put this together I'd like to find the long bed parts down south somewhere where there isn't so much rust. My ext cab has a decent cab and frame but the front fenders are not good near the bumper, so those would need to be renewed anyway. There's a long bed 5 speed 91 truck here locally FS for $650 but I'm concerned that it will have a lot of rust and I haven't gone to look at it yet. The nice thing is that it has the sealed beam front end so I could pilfer that for the project as well.

Thanks for the comments guys!

Steve

 

Is your truck 4wd? Mine is, and its one piece. The 2wd long bed reg. cab, I have no idea if they are 2 or one piece. That all being said, I thought the wheel base between the 2 were fairly close.
Also, consider gas tank placement. On mine, its kinda molded around one of the cross supports. (it that makes sense) Also, is the filler door the same distance from the cab to the filler door the same between beds?
And is the overhang behind the rear wheels the same length?
I think all of this would need to be considered if you try to extend your existing frame.
BTW I have mine all apart, from the cab back at this moment. If you need any pictures or measurements...... let me know.

 

My truck is 4x2 extended cab. I can't remember whether my 4x2 reg cab long bed trucks had a single piece driveshaft or not, that was a number of years ago. The wheelbase between the LB and the ext cab is close but not the same. The bed is an additional 18" longer but the difference in wheelbase between the two would be 12" so some is before the axle and some is after. If you take the difference between reg cab SB and LB and then apply that to the extended cab to get the added length you'll need for the wheelbase. Since the bed is fixed length I'd just leave everything on the bed alone including the fuel tank.

I have no idea whether I'll try to do this or not but it's an interesting thought experiment anyway.

Steve A