To sawp or not to swap...

[Tony Wells]

That is the question. I start with a 90 long bed and although part of this falls outside the official 88-98 range, half of this deal does so I'd like some opinions on it if you guys care to comment.

My 90 is a 2500 with a stock, old and tired 305 and a badly leaking front trans seal. I'm old and broke down (on disability even - bad back and deaf) so really would rather not pull the trans just for a seal. But recently, the pass side exhaust manifold either cracked under the heat shield or I burned through the gasket, so I need to do something. OK enough backstory. Except there is a liftgate involved that I have to keep on whatever truck I drive.

The guy I still do some work for has offered me a running 2000 GMC truck, but it has a heavy duty flat bed on it that I can't use. So my question is, can I move my old 90 model bed, with lift gate, to the later model truck chassis without tons of fab work. I have all the tools and shop to do the swap, even if it does take fab work (machine shop and fab is part of my career and I am a professional machinist) and a volunteer to keep me from really screwing up my back worse (hopefully). But I haven't taken any measurements at all to see where the mounting bolts fall, or if the fuel filler neck and hose are close enough to fit up. I guess it's about the same question as just replacing the normal bed on the newer truck with a 90 model bed. My options are kind of limited really. I like the old truck, but for one thing. It has no AC. Here in TX it's pretty rough to work out of in the summer without it. I've not ever had to do a bed swap, so not really sure how involved it is. I'm over 60 and been wrenching all my life so I'm sure I can do it, with some physical help, but if it's going to require a lot of fabrication, I don't think I want to. I'll then try to find a stock 2000 bed and just transplant the lift gate.

If I can't make this work easily, I really should pull the trans to re-seal it and replace the torque converter just because, while it's out. Then break all the manifold bolts off (j/k) and probably just replace the manifold if it's really cracked, although I could weld it. Or replace the gasket if that's what it is. I would then wind up with a usable, but hot, tired old Chebby truck. Even though it's high mileage (nearing 300k) it still pulls a trailer with a car on it just fine. It's been a durable old truck, but the work it needs is mounting up to a point I have to do something with it to keep it in service. It's just a work truck, and the old bed has a few whiskey dents, etc. But it hasn't ever left me on the roadside so I don't really want to get in to a newer fancier truck. I checked into an aftermarket AC, but they cost more than the truck is worth, so that's out. But I don't use it much, and I've suffered a few summers in it so I'm not wimping out just because of the AC. Just that, given a fair chance, I would upgrade to a newer truck to get it.

So what say ye, wise ones of GMT400.COM???

TIA,
TCW

 

[stutaeng]

Welcome aboard!

Is the 2000 truck with the flatbed also a 2500? If it's a 3500, it may be a "cab & chassis" frame, which is different than a regular pick-up frame. Compare the 2 frames, but if the have the same profile, they should swap easily. I'm assuming the 2000 is also a GMT400 as your 90? It's the same body style, right?

The cab & chassis does not have that curved frame profile behind the cab, rather, it comes out straight. So a regular truck bed is difficult, without a lot of fabrication. Probably just easier to get a regular bed.

Can you post some photos?

 

[geeeee89]

Honestly it seems easier to just find a bed and move the lift gate over to the newer truck. Sell the flat bed to cover the cost of the bed plus some. Then you'll have a newer truck to tow with and still get to keep your old one to drive around once you get it fixed (assuming keeping both is an option). I can't tell you how the bed mount locations differ between the two trucks though.

Too bad you're not closer to me, I'd be happy to help you get your 90 model fixed if I was close by.

 

[Tony Wells]

Welcome aboard!

Is the 2000 truck with the flatbed also a 2500? If it's a 3500, it may be a "cab & chassis" frame, which is different than a regular pick-up frame. Compare the 2 frames, but if the have the same profile, they should swap easily. I'm assuming the 2000 is also a GMT400 as your 90? It's the same body style, right?

The cab & chassis does not have that curved frame profile behind the cab, rather, it comes out straight. So a regular truck bed is difficult, without a lot of fabrication. Probably just easier to get a regular bed.

Can you post some photos?

First, thanks for the welcome! Glad to be here. I've been a lurker up until now and have found a lot of great info here, but found myself in a bit of a quandary on this one.

Yes, the 2000 GMC is also a 2500, a detail I omitted in my haste posting. The obvious difference is that the 2000 is an 8 bolt axle setup whereas the 90 is a 6 bolt. I am given to understand there may be some differences in actual duty rating between the two with the 8 bolt setup actually a bit heavier, while the 6 bolt sort of just a beefed up half-ton truck. Correct me if I am wrong. They are the same body style. I haven't crawled around under the 2000 model enough yet to compare; it's in the weeds at the moment. I tried to get it started today, but there seems to be a fuel delivery issue. It cranks, tries to run then dies immediately. It was last registered and on the road approximately in 2018 so could be simply bad gas. It has about 1/4 tank showing on the gauge, so I'll dump 5 fresh gallons in and see if it will run and move it. I have a covered slab at that site where I can do any work it needs and also get under it and take a few measurements to compare the two frames. I'm pretty sure this flat bed was added by the current owner, so I have a hunch it was a standard bed originally.

It is on a worksite where I contract some heavy equipment work (just the light stuff, and only a little of that) and will be there tomorrow so will try to get a few pics. Hopefully I can get it cranked and moved.

Honestly it seems easier to just find a bed and move the lift gate over to the newer truck. Sell the flat bed to cover the cost of the bed plus some. Then you'll have a newer truck to tow with and still get to keep your old one to drive around once you get it fixed (assuming keeping both is an option). I can't tell you how the bed mount locations differ between the two trucks though.

Too bad you're not closer to me, I'd be happy to help you get your 90 model fixed if I was close by.

That thought has crossed my mind. It should eliminate any question of fit. This is especially true since the 90 bed isn't in prime shape. One embarrassing dent came from backing up as close as possible to a Hogzilla tub grinder and running over a chunk of wood big enough to have to climb, but I was right on the end of that chunk and when I got centered on the top of it, it up-ended and the rear end of the truck slid off, right into the grinder. The grinder weighs about 80,000 lbs, so it didn't move, but pushed in a pretty ugly dent just above the left rear tire. It's double wall of course, so can't beat it out from inside, suction cups aren't strong enough to pop it out, and I don't have all the stuff to drill or weld studs and pull it out and fix it. It doesn't rub the tire, so I chalked it up to me not watching what junk I was backing into/over and have been just living with it. A new bed would cure that. Moving the lift gate and brake setup would be relatively easy.

I've really no need of the flat bed, except a distant desire to set up a light duty service truck and mount a welder and compressor on it. But then I believe I have access to a tool bed if I wanted to go that route. Not all that keen on setting myself up to work that much. My body is telling me I should be downshifting and slowing down, not gearing up for a future of heavy work.

I really can't justify having two trucks. I have a Ford E150 work van, a Chev box van (sits most of the time already), and a Jeep ZJ for running around, then the 2500 Chevy. Adding the GMC makes 5 vehicles for one driver and that may be over the top for a semi-retired guy who wants to slow down. On the other hand, since the old one does seem to take some abuse, like picking up stoopid dents, it makes sense to keep it, but just avoid stressing it by towing with it. I have a feeling it won't live nearly so long if I keep that up. But if I really want a nicer, newer truck (which I do) maybe it's just better judgement and discipline to keep from running all over rough ground that would serve me best. Not that the 2000 is pristine by any means. It's a work truck too, but just in much better shape.

And ameadows, I sure appreciate the thoughts on helping me get this worked out. I wish you were closer too lol. But I have a healthy younger brother who I'm sure would pitch in if it gets too tough for me. He's a decent wrench, although a Ford guy, but I don't hold that against him. We've collaborated on several projects over the years and it's never been a problem. Really they are all just machines to me. I'm a machinist by profession, so as they say, "parts is parts". But preferences are preferences too.

I think I'll start with just getting this Vortec started and moved into my temporary shop area to get some measurements and just see if this will even work. If I have to rebuild the 2000 frame, then I'll look for another bed. They are both fleet white, so there should be something available. The 90 can't be driven, but it's at my shop, so I can get it on a slab and do the same. I'll put up a few pics of both and then maybe you guys can comment a little more specifically.

Thanks for sharing the thoughts so far, guys.

TC

 

[stutaeng]

Ok, great. I don't think they made 2500 cab and chassis cab, so sounds like a regular truck that someone put a flatbed on. So maybe a hunt for a average bed and you can swap your lift gate into the '00?


What engine does the '00 have?

Generally, the 8 lug trucks are beffier than the 2500 with 6 lugs. The Vortec do have a bit more power, but also add the complexity of additional sensors. They are great engines, but can be a bit finicky sometimes.

If I could do a list of 3 weak areas of those engines I would say intake manifold gaskets, spider injectors and distributor. This is specific to the 4.3/5.0/5.7. Otherwise, great engines. Very easy to work with and parts are plentyful and very affordable.

Unfortunately, I don't know much about the the TBIs. My brother has a '90 C1500 that I sometimes help him on, as needed. They are much simpler to work on with less electronics...

Hopefully we can help you get your truck running again.

 

[Tony Wells]

It's the 5.7 Vortec. Not my favorite to work on, but when they are running right they are ok. I'll put out some feelers for a new bed for the 2000 today if I get a chance. That really make the most sense. If I can find one, that would or should eliminate any questions of fit, simplify the wiring, etc. Worst case might then be some alteration on the gate or hitch setup. I can live with that.

This same owner had a CNG service bed 99 with a 5.7 a while back. I un-converted it back to gasoline. That was sort of a pain, hunting down the parts that were removed to go with CNG. Was a nice clean truck and I almost bought it, but wasn't convinced about the work bed. I like my tools in side. I do some electronics based repairs also (security cameras and network stuff) and carry instruments that I wouldn't want exposed to all the humidity and condensation inside the toolboxes, plus the liftgate would have been quite the project to get on it. The toolboxes take up a lot of room and don't leave much free bed area. For me it just wasn't a good fit. I hope to get it running today after a PC board swap on a cardboard baler. I should have pics of the truck today.

 

[Tony Wells]

Sorry guys, no pics today. Hot jobs kept popping up. We sell a lot of heavy equipment in addition to trucks and trailers, and sometimes they aren't really ready, but someone comes up with cash and the crunch is on to fix whatever needs it. It seems to become part of the negotiations for the sale, so I was hopping, trying to get a couple of trucks patched up for pickup tomorrow.
Naturally my 90 is out by my shop, so I will get some pics of it up tomorrow, but the 2000 will have to wait.

 

[Nad_Yvalhosert]

@stutaeng wrote: I don't think they made 2500 cab and chassis cab, so sounds like a regular truck that someone put a flatbed on.

GM did indeed build such a rare bird. Had one yesterday at my shop for NY's required safety/emission inspection, otherwise known as a NYSI.

1998 GMC 2500, 2wd, single cab chassis frame, flat frame rails, service body, single rear axle, 8 lug semi-float, 8600 GVW, hydroboost brakes, 5.7 Vortec, 4L80 with 208k miles

I've been looking for 2500 or 3500 2wd longbed pickup for a project I have in mind. If this thing was a p/u, I'd have snapped it up a year ago when the owner was deciding whether to keep or repl the thing.

 

[David89gmc]

The beds are completely different so use your idea to "find a stock 2000 bed and just transplant the lift gate".

 

[Tony Wells]

You must be registered for see images attach

Right behind the cab, drivers side.

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Passenger side rear spring hanger area.

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Right rear, just behind wheel/tire.

I believe this truck frame was built for a flat bed. I haven't taken pictures yet of my '90, but I don't think the frame has a flat straight rail on top. I'll get a better look and a couple of pics of the same spots. Sorry about the weeds, but that's where it sits atm. Not the best pics in the first place.

I have a line on a 327 I can build to drop into my '90 and there is a trans with it. Might be a PowerGlide. I'll know next week. Even though the bed of my old truck is beat up some, it still has a (new price) $2400 lift gate, worth more than the truck. I may just fix mine and tough out next summer and then maybe sell it. I don't plan on needing a work truck after that, but I will always need a truck. Plus I want my next one to be a 4x4.

It's either something like that, or just get this 2000 3/4t and drive it with a flat bed and no lift. BUT, it does have AC And yes, I'm just getting old and soft.