Help on a Swap on 87 Square Body

[xxchier]

Not sure if this is the correct place to post this question. Let me know if not.

My grandson and I are in the first stages of swapping a 2018 LT into his 87 SWB. He has purchased an engine and now finds out there is much to do to make it work. Mainly all the change to install a power steering pump so he can still use the stock PS system. The 2018 Tahoe donor had electronic steering.
Any suggetions on best/or lower cost way to make this swap? Who to contact for best information?
Or should he look for a Tahoe frame to use? How much trouble/work will he get into trying to fit his 87 body onto a later model frame and what frame would you suggest? Any late model or stick with a Tahoe frame.
All suggestions are appreciated.

 

[dvdswan]

Did he get the PCM with wiring harness with the engine? Did he get the throttle pedal as well?

 

[eskimomann209]

Not sure if this is the correct place to post this question. Let me know if not.

My grandson and I are in the first stages of swapping a 2018 LT into his 87 SWB. He has purchased an engine and now finds out there is much to do to make it work. Mainly all the change to install a power steering pump so he can still use the stock PS system. The 2018 Tahoe donor had electronic steering.
Any suggetions on best/or lower cost way to make this swap? Who to contact for best information?
Or should he look for a Tahoe frame to use? How much trouble/work will he get into trying to fit his 87 body onto a later model frame and what frame would you suggest? Any late model or stick with a Tahoe frame.
All suggestions are appreciated.

Wait you mean you don’t just drop it in and the wires sprout into place and a fairy comes down and tunes it for you? What the fer heck?

Of course there’s “much to do to make it work.”
It isn’t as hard as say an LT swap (those were terrible ) but yes there’s much to do... and of course you didn’t choose to use a tried and true 5.3 swap where parts are a plenty... noooo you wanted to pilot this thing with the newest computer and the newest 6l60e transmission too I bet. Lmfao.

personally I don’t know what you mean by electronic steering I haven’t seen one that wasn’t hydraulic. You need to find a way to adapt the ps pump lines to match the steering gear box. I used a compression fitting for mine. It was cheaper and I haven’t had any issues. For the return line on the pump reuse one of the rubber hoses and a hose clamp. That should solve your pump/box issue. If it’s the variable assist power pump I’d just leave it unplugged and see how that works... it might make it into over boost tho... if it’s the style I’m thinking of. If it drives too squirmy I’d say buy an older pump if it’ll bolt up ( Chevy stuff usually interchanges). If yeh can’t figure out this part of the swap... there isn’t a frame swap in hell thats going to help... and to go for a frame swap to avoid the steering issue seems like a crazy complicated way to avoid that little problem. plus I dunno the age of yer granboy... but frame swaps take patience and some real welding skill. Not something I’d trust to just anyone.... Welding on a vehicle frame for a body that is being put into an 2018 LS powered engine... takes some serious know how.

 

[eskimomann209]

Pictures of the engine, accessories, wiring, anything you have would help

 

[Shorty81]

Or maybe drop in a engine of the correct era. Would be plug and play.

 

[xxchier]

Yes dvdswan, he did get the PCM, and throtle and wiring harness, but harness has be cut in one place but he has both parts. Could be a big splicing job though.

 

[RoryH19]

LS swaps are not easy or cheap. They take time, money and patients. You have the added pressure of installing one of the latest versions. Not only do you need to consider the above you need address the entire fuel system. I would suggest using a different PS pump from a 5.3 or 6.0. The lines will directly connect to the SWB steering box.
Another question is 2wd or 4wd as the signal to tell the ECU to shift the transmission comes from there. ECU needs to be flashed to remove security (vats) and downstream O2 sensors. So on and so forth. The amount of works adds up quickly.

I've done this swap on a k5 using a 6.0 Escalade engine and trans. See the link in my signature for some tips.

Good luck.

 

[eskimomann209]

Yes dvdswan, he did get the PCM, and throtle and wiring harness, but harness has be cut in one place but he has both parts. Could be a big splicing job though.

No no no no splices. You’ll have problems down the road. The computer needs whole wires to get proper signals. Splices increase resistance and throw things off. It can be done to test function... but after it should be replaced properly

 

[Poppy 87]

GM does in fact use electronic power steering in some full size trucks, actually going back to 2015. Your easiest solution would be to use a manual steering gear box for the 87. By the way, brake vacuum assist is provided by an engine driven pump.

Sent from my XT1254 using Tapatalk

 

[RecklessWOT]

personally I don’t know what you mean by electronic steering I haven’t seen one that wasn’t hydraulic.

Just because you haven't seen one does not mean they do not exist. This isn't even a new thing, it's been around a good 10-12 years, most auto manufacturers use it on at least some models at this point. It's f-ing stupid, but yeah it's a real thing. Just like drive by wire throttle, they're trying to take any sort of mechanical input out of the equation- even hydraulic.