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Looking for V8 into AWD info

4K views 39 replies 9 participants last post by  markmitch 
#1 ·
This is pertaining to the old style conventional small block Chevy, ie 350, 305, 327, etc. I need to know specifically how did you deal with the oil pan? Did anyone find an older style oil pan for from the older full front axle trucks? or did you have to fabricate one? Thanks Mark.
 
#2 ·
Mark how much can you spend on the pan an can you weld?
 
#3 ·
I can weld but not an oil pan that has to be leak free, I know JTR used to sell a pan for the swap but it is no longer shown on the site and I just received an email saying they only sell the part to be welded in. It has to be tig welded to get it to seal is what I read.
 
#5 ·
apparently there is a section of oil pan sold by JTR publishing to weld into the 4.3 steel pan to make it fit the V8 BUT you can no longer buy the 4.3 AWD pan new. So I guess I will have to grab one from pick n pull then take it to a machine shop to have it cleaned thoroughly then take it and the pan section to a welding shop to have it made. I find it hard to believe with all the V8 4x4 trucks made over the years that none will fit this project.
 
#6 ·
Since my AWD body is lifted.. when I put a V8 in mine I intend to lift the motor as well, and not screw with the pan. Something about a sectioned and divided pan bothers me. Raising the mounts shouldn't be difficult at all. I've read that 2 inches of engine lift should be adequate... but uncertain if that applies to Gen 1 V8 block. I'll probably borrow one of those plastic mock-up blocks (from a friend) to fit it for certain.
 
#7 ·
Mmusicman said:
Since my AWD body is lifted.. when I put a V8 in mine I intend to lift the motor as well, and not screw with the pan. Something about a sectioned and divided pan bothers me. Raising the mounts shouldn't be difficult at all. I've read that 2 inches of engine lift should be adequate... but uncertain if that applies to Gen 1 V8 block. I'll probably borrow one of those plastic mock-up blocks (from a friend) to fit it for certain.
Funny, Mmusicman that is what I started today. 2 inch is very close, so I decided to go 2.5 inches. Plus Im putting in a 246 Tcase and needed the room for the slightly different clock position. Second, if a rubber mount failed completely should still be safe, no hole in a pan.
 
#8 ·
Bigforkg said:
Funny, Mmusicman that is what I started today. 2 inch is very close, so I decided to go 2.5 inches. Plus Im putting in a 246 Tcase and needed the room for the slightly different clock position. Second, if a rubber mount failed completely should still be safe, no hole in a pan.
Excellent! But when I said 2 inches.. I heard that was the minimum.
With lots of body lift.. I have plenty of room to add an extra inch or so.

2.5 inches sounds perfect.
You will be the expert.
Please take plenty of photos and share! :D
 
#10 ·
but when you lift the engine higher doesn't that mean you need to also lift the transmission and T case? then will it not mess with the drive shafts , axle /angles and such? I am no expert but the drivetrain angles must be retained or modified to some degree to match up right?

PS: I was told the oil pan can also be brazed -not sure about this info as of yet though.
 
#11 ·
markmitch said:
but when you lift the engine higher doesn't that mean you need to also lift the transmission and T case? then will it not mess with the drive shafts , axle /angles and such? I am no expert but the drivetrain angles must be retained or modified to some degree to match up right?

PS: I was told the oil pan can also be brazed -not sure about this info as of yet though.
Are you going to lift the body? If your keeping it stock height dont bother get a RWD then. With the AWD and v8 you will be modifying more than you think.

Yes. You lift trans and Tcase. The front drive shaft on mine is 1.3 degrees from Tcase to front diff, not even going to worry about that. The rear may need a little adjustment have to see when it goes back in. No different than lifting and putting s10 springs in.

Im sure the pans could piece it together but not going to be cheap if you find someone who can actually do it right. And if it leaks start over.
 
#12 ·
OK Thank you for the info-added it to my notebook so to speak, I have it saved on my google docs and sent to my email just in case. I will be doing a 2" lift possible 3" replacing the bushings in the differential and I have to make the motor mounts anyway so I got a small block chevy that is junk just to trial fit everything. Which means the frame from the 98 AWD will be sitting in my yard while I make parts and trial fit them. Once I get the parts made some of it will be powder coated. I am eventually switching the t case to a 233 too. I have to take my 2 wheel drive 700R4 apart to swap the output shaft too. The Astro I am putting this into is my 89 rear drive RS shorty. I will look into the ideas you posted Today I will climb under the 98 donor van and measure everything in stock form for my notes too. Thanks for the great info, Mark
 
#15 ·
its basic info, nothing in any of my books tells about the oil pan except that the publisher sells a section that will have to be welded into a 4.3 pan then the holes will have to be redrilled to fit the 350. I am most likely going to do this mod since I am not lifting the whole drive train. I will be doing a 3inch body lift then add a leaf type rear suspension lift. since I have both sets of steel factory leafs from two different Astro vans.I already bought most of the parts to swap the u shaped piece out to a bracket made for other trucks. I just need to figure out how to re attach my rear swap bar to it.
 
#16 ·
what about Milodon or Moroso oil pans?? i haven't looked into them but they used to be a couple of the go-to companies for engine swap stuff. maybe get lucky with a V8 Vega pan?? by the time a shop cuts up a pan & welds in the JagsThatRun extension patch the cost advantage would probably be gone. it might also be better to alter the sump of a pan rather than having 4 butt welds running across the gasket.
 
#17 ·
markmitch said:
..I am not lifting the whole drive train. I will be doing a 3inch body lift..
The "body lift" is what gives you room to do the engine lift.
Then there's no need to cut up and weld oil pans.

This is how I will be doing mine
 
#18 ·
markmitch said:
its basic info, nothing in any of my books tells about the oil pan except that the publisher sells a section that will have to be welded into a 4.3 pan then the holes will have to be redrilled to fit the 350. I am most likely going to do this mod since I am not lifting the whole drive train. I will be doing a 3inch body lift then add a leaf type rear suspension lift. since I have both sets of steel factory leafs from two different Astro vans.I already bought most of the parts to swap the u shaped piece out to a bracket made for other trucks. I just need to figure out how to re attach my rear swap bar to it.
Ahh, maybe they updated it from the original. I thought originally they said to just cut two 4.3l AWD oil pans and join them together.
 
#19 ·
Yes I got the same info from another site, the one guy took two oil pans from S-10 4x4 trucks and made one v8 oil pan. He also said using two pans requires one weld whereas using two pans only requires one weld so less cahnce of problems. Mark
 
#22 ·
You may want to consider dropping the front dif a little to gain som clearance. Super simple and comes with the added benefit of increasing suspension travel and reducing half shaft angles.
 
#23 ·
I will look into that too, I was thinking of raising the engine 1/4 inch or so, then the same for the transmission/transfer. so if I changed the front diff I would have to figure out the math side of it and to be honest that is my worst subject. But in simple terms I can measure my 2003 angles and all that to get a base to go from.
 
#24 ·
So I found this site and a bunch of good info from it. I believe I will need to buy at least the front drive shaft from a 99 to 2004 AWD Astro to make it work with the NP231C transfer case. I think there is a 2000 AWD at pnp in Stockton CA so I will have to make another trip soon.
 
#25 ·
OK,Am tired,and have a few minutes.Here is how I did my 94,many years ago.I used a 231 case,front shaft and snifter that bolts to the t/case.That listing link you posted is not exactly right,as there were many configurations,back then.The 95 case I used has a yoke output.The front shaft "fits", except is too short,I had it lengthened.The stock astro shaft fits ok,except it has more exposed,less spline engagement.Has been in there all these years,just fine.However,even a small lift kit,you would run the chance of it coming out,would have to be lengthened.I used the stock blazer shifter,just cut a notch in the floor.It only sticks up about 4 inches,and I need both hands to be able to go to low range.Which I have rarely done,usually at a boat ramp or pulling someone stuck,out.If I ever need to change it,there are plenty of s10/blazer/jeep factory cable shifters out there that will work fine.But,for what I use it for,I am usually just reaching down and bumping it into 2wd--4wd.I mounted the vac diaphragm assembly,for the front axle disconnect,up behind the rear of the rf wheel well,and ran vac hoses to it.The only problem- the t/case was just thousands away from the top,there is a floor support beam.No practical fast way to lower it,except cut off mount and reweld.So what i did was notch out part of that support beam,then weld a piece of flat iron above it,for support.That way it does not hit on bumps and such.But a lift kit would cure that also.Just remember,you probably will have to have the rear shaft lengthened if going with a lift kit.More info for your collection.
 
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