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Removing subframe for engine swap

12K views 81 replies 22 participants last post by  M_a_t_t 
#1 ·
After weeks of slow, interrupted progress, I started lifting the body off the subframe. So far so good. Going to lift some more and double check that everything is disconnected. I could not find a video guide on this process, so I got some tips here and mostly I'm figuring it out as I go.

It was a weird feeling undoing the six 18mm (and 21mm) bolts that stop the van breaking in half, then seeing the body lift off the subframe. I'll post more progress pics as I go.
 

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#4 ·
Help! I'm stuck. The subframe bolts are out and everything is disconnected I think. But the subframe isn't dropping like I expected. Something is holding it up off the wooden frame I planned for it to rest on. It's concerning because I don't want to break anything and it could drop suddenly. What am I missing?
 

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#6 ·
Took another look. Wiring harness is moving so it's not that (not above the engine anyway. All the hoses were disconnected I think although I disconnected some at the other ends and left them attached to the engine because it seemed the simplest approach. I'll keep hunting.
 
#8 ·
OK this is my list: brake lines to rear brakes, hoses, battery cable to starter, wires, rear drive shaft, steering column, radiator, & shroud, e brake cable, trans cooler lines, oil cooler lines if you have them, brake lines from the anti lock, starter wires, fuel lines, I think that should do it.
 
#9 ·
Thanks Stent, please send it when get a chance.

Markmitch, you may have it - I didn't disconnect the brake cable. Didn't realise I had to as it goes from the body to the back brakes. I'll look into how to disconnect it. It would not surprise me if that's the answer as the cable may be the only left that's strong enough to hold the weight.
 
#10 ·
I can't begin to tell you how EASY it was to pull my motor out the front!
Very little time underneath the van too, which is a big deal for me these days.
For me it's a simple half day one man job. Then when out, I roll the van back into the garage.
Sorry I can't offer any helpful suggestions.. but I do wish you the best in this big adventure.

IMG_0039aV6EngineLift92Astro.jpg
 
#11 ·
stent said:
hey angrypunk,
i'm at work now - i have an old Haynes manual at home that i believe has a checklist for getting the frame off. i'll bring it to work tomorrow, scan the info and post it here for you...
the old haynes manual said for anything newer than 1995 take the van to a shop & have them do it - HAHAHA

the scans i'm adding instead are from the 1999 factory service manual. i'm going to post a page & see how it looks, then add the rest....i think your thread here would be a good place to post the official version for future reference.
Scan1.jpeg


MORE :
Scan1 1.jpeg

Scan1 2.jpeg

Scan1 3.jpeg

Scan1 4.jpeg

Scan1 5.jpeg
 
#12 ·
markmitch said:
OK this is my list: brake lines to rear brakes, hoses, battery cable to starter, wires, rear drive shaft, steering column, radiator, & shroud, e brake cable, trans cooler lines, oil cooler lines if you have them, brake lines from the anti lock, starter wires, fuel lines, I think that should do it.
markmitch, you nailed it. There's a weird protrusion in the subframe that caught the brake cable on the way up. I undid the bracket and pushed the cable aside. Then reraised the body and bingo - the subframe dropped down into the cradle I built for it.

There was one extra wire I missed from the wiring harness so I unplugged that. So I'm in business. I will figure out how to move the subframe tomorrow and I can get to work on the swap.

Musicman, I have no doubt the front way is easier but I wanted to keep the new engine and transmission together and from the research I did, that process seemed easier with the body off. Now that I have taken the body off I agree it is a f@£& tonne of work. But I am loving the access so everything and I'll use the opportunity to paint the subframe and under the van as well.

Depending on the cost of parts I may do valljoints while I'm at it. But honestly, I could keep replacing things until the vows come home and I need a working vehicle so I'll need to get it running soon if possible.
 
#14 ·
Thanks for asking Astrowill :)
Yes, major progress. Got the subframe out. It was rough. Despite all the efforts to date I still found 2 new wiring harness connections plus another hose I missed. I made the brake lines harder than it needed to be. Should have disconnected them at the abs module I think. But the subframe is completely out now.

They say it requires two people. I can attest it can be done with one, but it's not pretty. Took a lot of lateral thinking and problem solving. No doubt there are better ways but I blundered through as best I could. It was one of the scariest things I've ever done, (and I survived Afghanistan).
 

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#16 ·
So tell us... how DID you wheel the sub-frame from out under the van?
How did you get past your engine hoist?
I also assume your going to need this hoist to pull the engine off the subframe?
Looks like it's going to be even MORE insane fun getting it back in...
 
#17 ·
So I got the body high enough to clear the engine (left air intake and dipstick tubes on because I couldn't figure out how to remove the latter). Then put blocks and 6 tonne axle stands under the body. Lowered the hoist and pulled it out of the way. Then I put four logs left to right and three boards on top of them. Jacked up the subframe, removed the axle stands, lowered the subframe on to the boards. Then I moved the front chock on one wheel forward 15cm (6") and pushed that wheel forward (levered it forward when necessary), then switched and did the other side. Repeat until subframe is completely clear of the body, occasionally moving a log from the back to the front of the boards (how they built the pyramids).
Yes, plan is to use the hoist to remove the old engine (with tranny and transfer case), swap a few parts, and drop the new driveline in, then put it all back together. Old engine has 500k Kms on it but some new parts.

Next steps are to clean up the new engine, replace the valve cover gaskets, possibly oil pump. Swap the starter and alternator because they are newer parts on the old engine. Also have to switch some or all of the distributor. It got cracked by the junk yard. I have a whole new distributor I had planned to put on my 03 RWD - would it work on the '99?
Oil pan and power steering pump need swapping too. I will paint the subframe and under the body while I have it off.
Based on current progress it wil take me until July or August to finish.
 

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#18 ·
Congratulations on surviving the subframe extraction AND Afghanistan!
Both oil and trans dipsticks just pull up out of little sockets once you have their brackets unfastened from the block. If the trans is completely full of ATF then you will have a few cups puke up out of the top of the trans when you pull that dipstick.
Air intake horn comes off easily once you see how it works. You can probably tell now that you can see the rear side of it.
Taking the front wheels off but still doing the log and board thing will allow you to not have to raise the body as high.
So when it goes back in maybe if you do all of that you can reduce the height you have to lift the body by 10-12".
If you take the two brake lines off at the ABS module you will almost certainly have to have the ABS module bled by someone with a tech 2 computer. If you can keep the lines on and keep air out of the ABS module you MIGHT luck out and not have to bleed it.
 
#19 ·
Thanks Sparky :)
Good tips on the dipsticks. I'll do that towards the end so they're safe while I'm moving the blocks.
It never occurred to me to take the wheels off but that's logical and I will try it on the way back in.
Excellent news on the abs module. I messed around a lot to keep them attached and felt foolish at the end. But it sounds like I did the right thing, albeit through laziness.
 
#20 ·
AngryPunk said:
It never occurred to me to take the wheels off but that's logical and I will try it on the way back in.
loved your pics of the van & frame separated !!!
i seem to recall reading somewhere here about using wheels without any tires on them to help roll the frame around.
the bare wheels and a heavy swivel caster bolted to the rear of each frame rail might help a lot to scoot it around on the floor.
is your shop built so you could hang the nose of your van on a chain hoist from the ceiling & lower the van onto the frame??
:action-popcorn:
 
#21 ·
Thanks Stent :)

I have some rims without tyres and I thought about using them under to subframe but I was concerned about it rolling too quickly. Heavy casters would be good. I tried a trailer wheel but could not bolt it on. So I resorted to the logs.

Plan is to use the same hoist to switch motors then use it to raise the van again and I'll roll the subframe under and lower it on. It's going to take weeks. I'll keep posting progress pics
 
#25 ·
This isn't easy, wish I could do the same, hope it goes smoothly!
:action-popcorn:
 
#26 ·
I used an engine hoist and run a cable through the radiator support. Then blocked up the body with stacks of wood removed the engine hoist. And pulled the sub frame out. You have to get the top of the motor clear of the front radiator support so the original wheels and tires will clear ok. If I remember I thought I had mine up enough but I had to jack each side of the body up and add more blocking to clear the dip stick's transmission and oil they stick up higher than any thing else.
I'll try to attach a couple photos.
They may?? Be in my gallery here or on another hard drive from 8 years ago.
When I pulled mine it wasn't too difficult at all it rolled real easy fastened a 4X4 under the back cross member and screwed two casters from Habror F on the bottom But they were cheap and the caster wheels worked ok but the metal part folded when I pulled the assembly across the yard
 
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