body swap thread. gmt400 on gmt800 chassis

[96k1500]

So its already been said that the frame is longer and body mounts are obviously in the wrong spots but arent the gmt800's also a little bit wider?

 

[great white]

You guys are Also missing the fact that He wants to build a pre-runner style truck too i think Which the GMT800 has more suspension parts available for

Ah, yes. You're right.

He's that guy.

I missed that.

carry on....

 

[Hezsus]

one of those gmt800 frames with that motor without the sparkplugs would cost well over twice as much as just a 6.0 or 5.3.... i love that idea but thats def outa the pocket range...

whatll need to be done to the radiator supports? you mean to adapt my grill and headlights etc?

steering can be adressed with some of my shop resources and a welder

shift linkage im sure i can machine something up for

firewall clearance hopefully wont be a problem since they use to stick 454s in this style.... hopefully...

and whats different about the gas tank position?

I havent read all the other posts so this may be covered. but yes the headlights , grille, rad, and all that will need some fab work. and i'm not 100% sure on the gas tank, it would be just the filler tube (simple) that many need moved.
I'm interested to see this project but to be honest If my frame rotted out (its getting thin.. for real) I would put another gmt400 under it in a heartbeat or make my own frame, since I have a family run fab shop (waterjet and all).
BUT, my old (and a little sloppy) 5.7 beats my friends 09 (same truck just newer with the 5.3) and keeps up to another friends 2013. But i get smoked by a 97 ecsb 2wd. So if you keeping the gasser, aside from a little mileage I honestly dont see any substantial gains. The 4l60e (your trans) is used on the gmt 800 trucks as well (not 100% but pretty sure) and do you really wanna ditch you 350. a few grand can turn it into a real nice 383 that you can daily.
I do prefer disk brakes, but thats a matter of a rear end (really just the backer plates), not the frame.
I tow a 10k lb trailer with my truck regurlarly and my thin fram is holding up (not fine.. i have to modify where i put the airbag mounting as they are twisting the frame) but nothing critical.
If you have all good body parts I think your money and time may be better spent doing a ground up resto (since thats basically what it is either way) on a gmt400 and beefing it up rather than cursing when you have to drop the trans when the linkage isnt right or try to flex and drop the drivshaft (unlikley but its very upsetting to see). Just so many things that could go wrong.


ON THE SAME BUT DIFERENT NOTE

look at a gmt400 heavy half or 3/4 or 1 ton frame/axle. better brakes, front and rear end, bolt in a 4L80e trans (better than the 4l60e). you can even throw a locker in the front diff of the 3/4 or 1 tons.
The frame will accept your body no problems, and you can keep your current motor/trans if you like. or upgrade. there is, around here anyways 1 tons and 3/4's going for dirt cheap cause of the diesel engines in them. trucks are still like mint, just need a "new" engine.

 

[Hezsus]

You guys are Also missing the fact that He wants to build a pre-runner style truck too i think Which the GMT800 has more suspension parts available for

This I did miss.
There is a few pre runner gmt400's (or were) on here check them out as I know little about those mods.

 

[benz88]

This I did miss.
There is a few pre runner gmt400's (or were) on here check them out as I know little about those mods.

yeah, but theres more company's who make Suspension pieces for the 800's then the 400's

 

[Darkrider]

Ah, yes. You're right.

He's that guy.

I missed that.

carry on....

Was gonna say something about that but chose to be nice lol

I havent read all the other posts so this may be covered. but yes the headlights , grille, rad, and all that will need some fab work. and i'm not 100% sure on the gas tank, it would be just the filler tube (simple) that many need moved.
I'm interested to see this project but to be honest If my frame rotted out (its getting thin.. for real) I would put another gmt400 under it in a heartbeat or make my own frame, since I have a family run fab shop (waterjet and all).
BUT, my old (and a little sloppy) 5.7 beats my friends 09 (same truck just newer with the 5.3) and keeps up to another friends 2013. But i get smoked by a 97 ecsb 2wd. So if you keeping the gasser, aside from a little mileage I honestly dont see any substantial gains. The 4l60e (your trans) is used on the gmt 800 trucks as well (not 100% but pretty sure) and do you really wanna ditch you 350. a few grand can turn it into a real nice 383 that you can daily.
I do prefer disk brakes, but thats a matter of a rear end (really just the backer plates), not the frame.
I tow a 10k lb trailer with my truck regurlarly and my thin fram is holding up (not fine.. i have to modify where i put the airbag mounting as they are twisting the frame) but nothing critical.
If you have all good body parts I think your money and time may be better spent doing a ground up resto (since thats basically what it is either way) on a gmt400 and beefing it up rather than cursing when you have to drop the trans when the linkage isnt right or try to flex and drop the drivshaft (unlikley but its very upsetting to see). Just so many things that could go wrong.


ON THE SAME BUT DIFERENT NOTE

look at a gmt400 heavy half or 3/4 or 1 ton frame/axle. better brakes, front and rear end, bolt in a 4L80e trans (better than the 4l60e). you can even throw a locker in the front diff of the 3/4 or 1 tons.
The frame will accept your body no problems, and you can keep your current motor/trans if you like. or upgrade. there is, around here anyways 1 tons and 3/4's going for dirt cheap cause of the diesel engines in them. trucks are still like mint, just need a "new" engine.

I agree with this plan!

Sent from the middle of nowhere

 

[great white]

Was gonna say something about that but chose to be nice lol

Sent from the middle of nowhere

No, you're reading something in to my post thats not there and giving everyone else the same negative impression of it.

 

[TylerZ281500]

thats alot of down time to swap entirely different frames and such. 80s solid axled frames are quite popular swaps on gmt400s ive seena f ew of those. but theres no substantial advantage to a 800 frame swap, the fames and suspensions arent all that much better, buy a rust free truck, save up for some 800 knuckles and rear end run both disc and get a 800 master cylinder, swap engines, swap to a 4l80e and a 14bolt, then work on your long arm prerunner suspension if your still gung ho about it.

you say you can do a frame swpa like that so why bother buying a prerunner kit? if you say you have the talent you have then building something like longer arms and stuff shouldnt be of any issue, hell why not just 4 link the rear while your at it.

if you try swapping to the 800 frame who says the ls1 and dash cluster is nicely going to meet with the body harness and such of a 400? its just cheaper and simpler to swap engines alot of people have done it so you can get a rough estimate and stick within the range rather closely. otherwise the saying goes, once you found your budget double it and tiple it and theres the range of what youll actually spend.

 

[Horns]

thats good for the new Gm trucks. if i could afford one id buy one.

im sorry to argue with you but ive watched a 2500hd single cab long box take a gmt400 2500 extended cab long box backwards and all over the place. the 6.0 in that chassis was an uncomparable matchup to the gmt400... so if the chassis isnt more rigid, how the hell did that workout? must be that nearly identical suspension then....

as much as you want to argue with me, youre not the one doing it and my question wasnt for you to give your opinion, its to address how to go about doing it. so unless you have some constructive ideas, id like it if you'd back off on the sarcasm and negative comments. thanks

I wasn't arguing motor. A motor swap in the original frame would be a much more economic idea.

You guys are Also missing the fact that He wants to build a pre-runner style truck too i think Which the GMT800 has more suspension parts available for

If the dude has the skill to put a 400 on an 800 chassis, then a full tube frame build would be no problem for him and would suit his needs much better.


~Via Mobile \,,/

 

[Van Gui1d3r #838]

I wasn't arguing motor. A motor swap in the original frame would be a much more economic idea.



If the dude has the skill to put a 400 on an 800 chassis, then a full tube frame build would be no problem for him and would suit his needs much better.


~Via Mobile \,,/

only problem with that is itll never be street legal in new york. and frame mods are against inspection laws. hence why i have to do something about my frame either way. i gotta look into a few things, i may offer my truck and my tracker in trade for another 400 hopefully in better condition an so on and then i can look into doing and ls swap... otherwise i do wanna attempt this. especially because of the lack of support, i really think its more than possible...