4X4 700r4 question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

JayDubBlazer · 02-25-2008, 10:01 PM

Ok guys, and gals. I did a search on swapping out the 350 for a 700 but didn't find much information on how to do it with a 4X4. I saw that the 700 is 1-3/4" longer. The question is do I move the engine forward or the transfer case backwards? Or a combination of the two. I would like to move the engine forward because the way it sits now the HEI rubs slightly on the firewall. Thanks any help will be appreciated the frame is going to the body shop tomorrow.

extd56 · 02-25-2008, 10:24 PM

If you have room I would move it forward. You will also save money by not having to make a new front driveshaft and shorten the rear one.

ckhd · 02-25-2008, 10:49 PM

I did the 350 to a 700r4 swap in my '72 'burb.

I posted some of my experiences back in 2005. I think it should answer many of your questions. Here's the link: My 700r4 experiences

1969k10stepside · 02-25-2008, 10:50 PM

Move the motor forward...

ckhd · 02-25-2008, 10:57 PM

I guess one thing that thread didn't really address is the motor mounts. I moved the crossmemeber that the mounts are on forward. I had to drill new holes to mount the crossmember in. Not a big deal, but it's 8 new holes in the frame. Measure at least twice, so you only have to drill once. I have 10 new holes in my frame!

Oh, and I did have to trim my fan shroud a touch for the power steering pump and for the harmonic balancer. Not much, just a couple little notches, and it was easy to do.

If you have any more questions or specific questions, ask. I might not see this thread again (I don't come by as much as I used to), so if you ask me something and I don't reply, PM me and I'll come back and find the thread.

**hilljob26** · 02-26-2008, 01:21 AM

After Reading That,do I Need A Different Adapter Or Will My Th350 To Np208 Transfer Case Adapter Work

6872xtc · 02-26-2008, 02:44 AM

remember to watch oil pan to front diff clearance if the truck does not have a lift, it might be fine, but remember to check for suspension movement.

ckhd · 02-26-2008, 09:29 AM

Not sure about the np208, but whoever you get your tranny from should know. If they don't, I'd be a little nervous about getting one from them.

I didn't have any problems with oil pan clearance, and I'm stock height. I thought I'd have front driveshaft vs. tranny pan issues, but there actually was plenty of room.

duallyjams · 02-27-2008, 06:09 AM

I read on a different board that a th350/np208 and a 700r4/np208 adapters are different. Do you already have what you need or just researching.

JayDubBlazer · 02-27-2008, 08:06 AM

no i am in the process of getting one, I will probaly give bowtie a call tomorrow

02-25-2008, 10:01 PM	#1
JayDubBlazer go cyclones Join Date: Jun 2003 Location: Ames, IA Posts: 1,883	4X4 700r4 question Ok guys, and gals. I did a search on swapping out the 350 for a 700 but didn't find much information on how to do it with a 4X4. I saw that the 700 is 1-3/4" longer. The question is do I move the engine forward or the transfer case backwards? Or a combination of the two. I would like to move the engine forward because the way it sits now the HEI rubs slightly on the firewall. Thanks any help will be appreciated the frame is going to the body shop tomorrow. __________________ Wes PROJECT OLE GREEN 1972 Blazer 4X4 350/700R4 2017 Silverado LT

02-25-2008, 10:24 PM	#2
extd56 Senior Member Join Date: Nov 2004 Location: Vacaville, CA Posts: 2,272	Re: 4X4 700r4 question If you have room I would move it forward. You will also save money by not having to make a new front driveshaft and shorten the rear one.

02-25-2008, 10:49 PM	#3
ckhd Registered User Join Date: Oct 2000 Location: St. Johns, Arizona Posts: 2,660	Re: 4X4 700r4 question I did the 350 to a 700r4 swap in my '72 'burb. I posted some of my experiences back in 2005. I think it should answer many of your questions. Here's the link: My 700r4 experiences __________________ my 2¢ - t.i.o.l.i. Bowen 1968 K20 fleet 1969 K10 swb fleet 1972 K10 Suburban 1972 C10 lwb step 1992 K1500 'burb 1995 K2500 'burb 1997 C1500 'burb 1999 K1500 2000 K1500 'burb Why do I own so many Suburbans?

02-25-2008, 10:50 PM	#4
1969k10stepside Registered User Join Date: Mar 2006 Location: USA Posts: 21,019	Re: 4X4 700r4 question Move the motor forward... Last edited by 1969k10stepside; 02-25-2008 at 10:50 PM.

02-25-2008, 10:57 PM	#5
ckhd Registered User Join Date: Oct 2000 Location: St. Johns, Arizona Posts: 2,660	Re: 4X4 700r4 question I guess one thing that thread didn't really address is the motor mounts. I moved the crossmemeber that the mounts are on forward. I had to drill new holes to mount the crossmember in. Not a big deal, but it's 8 new holes in the frame. Measure at least twice, so you only have to drill once. I have 10 new holes in my frame! Oh, and I did have to trim my fan shroud a touch for the power steering pump and for the harmonic balancer. Not much, just a couple little notches, and it was easy to do. If you have any more questions or specific questions, ask. I might not see this thread again (I don't come by as much as I used to), so if you ask me something and I don't reply, PM me and I'll come back and find the thread. __________________ my 2¢ - t.i.o.l.i. Bowen 1968 K20 fleet 1969 K10 swb fleet 1972 K10 Suburban 1972 C10 lwb step 1992 K1500 'burb 1995 K2500 'burb 1997 C1500 'burb 1999 K1500 2000 K1500 'burb Why do I own so many Suburbans?

02-26-2008, 01:21 AM	#6
hilljob26 Registered User Join Date: Dec 2004 Location: Gypsum Kansas 67448 Posts: 1,681	Re: 4X4 700r4 question After Reading That,do I Need A Different Adapter Or Will My Th350 To Np208 Transfer Case Adapter Work __________________ 21 2500hd duramax 58 apache HILLJOB GRAPHIX--for all your graphic needs My build thread http://67-72chevytrucks.com/vboard/s...d.php?t=542497 LS ENGINE SWAP INFORMATION THREAD http://67-72chevytrucks.com/vboard/s...d.php?t=377348 4l60 to an NP205 http://67-72chevytrucks.com/vboard/s...43#post3697343

02-26-2008, 02:44 AM	#7
6872xtc Registered User Join Date: Jan 2006 Location: Grand Jct.,CO Posts: 59	Re: 4X4 700r4 question remember to watch oil pan to front diff clearance if the truck does not have a lift, it might be fine, but remember to check for suspension movement.

02-26-2008, 09:29 AM	#8
ckhd Registered User Join Date: Oct 2000 Location: St. Johns, Arizona Posts: 2,660	Re: 4X4 700r4 question Not sure about the np208, but whoever you get your tranny from should know. If they don't, I'd be a little nervous about getting one from them. I didn't have any problems with oil pan clearance, and I'm stock height. I thought I'd have front driveshaft vs. tranny pan issues, but there actually was plenty of room. __________________ my 2¢ - t.i.o.l.i. Bowen 1968 K20 fleet 1969 K10 swb fleet 1972 K10 Suburban 1972 C10 lwb step 1992 K1500 'burb 1995 K2500 'burb 1997 C1500 'burb 1999 K1500 2000 K1500 'burb Why do I own so many Suburbans?

02-27-2008, 06:09 AM	#9
duallyjams Registered User Join Date: May 2007 Location: Deale Md Posts: 4,663	Re: 4X4 700r4 question I read on a different board that a th350/np208 and a 700r4/np208 adapters are different. Do you already have what you need or just researching. __________________ James 63 GMC V6 4speed carryall 65 chevy swb bbw V8 auto 68 K20 327/4 speed, buddy buckets 2002 GMC CC Dually Duramax 64 GMC lwb 3/4 V6 4speed SOLD 66 GMC swb bbw buddy buckets SOLD IG duallyjams The only thing that stays the same is constant change!

02-27-2008, 08:06 AM	#10
JayDubBlazer go cyclones Join Date: Jun 2003 Location: Ames, IA Posts: 1,883	Re: 4X4 700r4 question no i am in the process of getting one, I will probaly give bowtie a call tomorrow __________________ Wes PROJECT OLE GREEN 1972 Blazer 4X4 350/700R4 2017 Silverado LT



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