Turning a C-20 into a K-20 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

1974ChevyC10 · 10-03-2007, 04:55 AM

ok my dad has 73 2wd 3/4 ton which has been sitting for the last 5 years.i would like to buy it from him and turn it into a K-20.truck originally came with a 454 and TH400 and if i recall its a cheyenne super so its pretty well loaded well as loaded as you'll get for 73 anyway.truck currently has no motor or trans.my plans are to add a front axle,4 inches of lift,33 or 35 inch tires,unsure on the motor but ill add a 700r4 for better driveability,not sure which tcase to use and the rest will be determined later.so my questions are what would be a good gm front axle to use,which would be the best tcase behind an auto trans,what other situations will i come across in turning a C-20into a K-20.

earl87gta · 10-03-2007, 06:29 AM

Best transfr case is a NP205 best axles would be Dana 60 front and 14blt rear.

Burt4x4 · 10-03-2007, 10:50 AM

Yup, get a 1Ton donor 4x4 and swap it in.

toomanytoyz · 10-03-2007, 09:48 PM

If you are Intent on Doing this, I feel best Route would be to Find a Donar Frame & Swap Body Over.

Much Easier than trying to add Axle's to your 2x4 Frame...........

Good Luck, Rick

earl87gta · 10-04-2007, 01:06 AM

I think adding 4wd axles to the 2wd frame is easier then swaping bodys unless you are planing on doing a frame off resto any way.

**Dieselwrencher** · 10-04-2007, 10:09 PM

I converted a 1976 C30 from 2wd to 4wd and it was really simple. I took a 4" square tube 1/4" wall, measured and placed the spring hangers where a 4x4 trucks are. Then I did some measuring to find the axle center line and drilled a 5/8 hole in my tube and it so happened that there was already a hole in the frame so I bolted it down. Then I welded it to the frame to ensure it wasn't going anywhere. I did some more measuring and cut a hole in the rear part of the frame below the firewall for a 4x4 shackle. I went to my buddy's junk yard and got the cast shackle mount from a full time rusted out turd. I then made sure it was square and drilled four more holes and bolted it on using grade 8 bolts. I made the shackles from 1"x5/16" flat stock. I didn't make the shackles until I had the leaf springs on and the axle under it so I could get the truck level. I used 6" lift springs and with the 4" tube it is 10" of lift. I used a 4wd steering box and the rest is pretty easy from there. Oh one more thing, I did use the engine crossmember from the K20 as well because you will get rid of the 2wd one.

**Dieselwrencher** · 10-04-2007, 10:18 PM

For the rear I used spring hangers from a 4x4 truck also because the 2wd ones were a lot shorter. I kept the 2wd leaf springs and did a shackle reversal on the rear and used a 4" lift block. My friend has a 1981 3/4 ton with a 10" lift and 36's and my truck sits about 1 1/2" taller than his. Here are some links to some pics.

http://i191.photobucket.com/albums/z...s/100_0456.jpg

http://i191.photobucket.com/albums/z...s/100_0453.jpg

http://i191.photobucket.com/albums/z...s/100_0536.jpg

I will try to find some pics of the front set up for ya.

earl87gta · 10-05-2007, 03:25 PM

do a serch ob b-52 or diy4x and they make every thing to do the convertion

*FormerMember* · 10-08-2007, 11:11 AM

Quote:

Originally Posted by earl87gta

do a serch ob b-52 or diy4x and they make every thing to do the convertion

Yep. This is what I did on my 71 C30.

www.diy4x.com

I used the Beyond B52's kit for a first gen.

Uses a rear spring in the front for 4" of lift and a very nice ride.

earl87gta · 10-08-2007, 03:12 PM

I think Im going to copy your Idea grendel but Im going to shorten the 1ton frame to work with my burb.

*FormerMember* · 10-08-2007, 10:35 PM

Quote:

Originally Posted by earl87gta

I think Im going to copy your Idea grendel but Im going to shorten the 1ton frame to work with my burb.

That works, I am using a 1 ton frame on my C/k30 conversion.

earl87gta · 10-09-2007, 01:15 AM

Im going that route in case I do get a 6bt to put in the burb. Plus braging wrights to say I have the only true 100% 1 ton 68 burb

**Dieselwrencher** · 10-09-2007, 03:19 AM

If you need any info on swapping a 6bt in let me know, I have done many diesel conversions. I am currently working on a 1991 f350 with one.

earl87gta · 10-09-2007, 03:44 AM

Cool thanks I have a 6.2 I was going to put in it but Im watching for a 6bt at a good price to use instead. if I dont find one by the time Im ready for the engine the 6.2 will go in.

**Dieselwrencher** · 10-09-2007, 03:49 AM

Keep an eye on ebay I saw a 94 p pump engine probabally a 160hp unit with a nv4500 5 speed with a starting bid of 1500 and no one had bid on it as of then. That is a steal of a deal.

earl87gta · 10-09-2007, 04:15 AM

The cheapest one I found here was 3k with no trans.

**Dieselwrencher** · 10-09-2007, 04:28 AM

Here is an ebay link to one right now. It would be a good start.

http://cgi.ebay.com/ebaymotors/5-9-C...QQcmdZViewItem

**Dieselwrencher** · 10-09-2007, 04:35 AM

Here is another
http://cgi.ebay.com/ebaymotors/CUMMI...QQcmdZViewItem

earl87gta · 10-09-2007, 12:40 PM

I bet shipping would be a lot of $$$$
1974ChevyC10 sorry about the high jack.

10-03-2007, 04:55 AM	#1
1974ChevyC10 Overworked and Underlaid Join Date: May 2002 Location: Flagstaff,Arizona Posts: 1,279	Turning a C-20 into a K-20 ok my dad has 73 2wd 3/4 ton which has been sitting for the last 5 years.i would like to buy it from him and turn it into a K-20.truck originally came with a 454 and TH400 and if i recall its a cheyenne super so its pretty well loaded well as loaded as you'll get for 73 anyway.truck currently has no motor or trans.my plans are to add a front axle,4 inches of lift,33 or 35 inch tires,unsure on the motor but ill add a 700r4 for better driveability,not sure which tcase to use and the rest will be determined later.so my questions are what would be a good gm front axle to use,which would be the best tcase behind an auto trans,what other situations will i come across in turning a C-20into a K-20. __________________ I'd rather push a Chevy than drive a Ford The Beast-1978 C10 LWB Red-1978 C10 LWB (Uncle Mike)Michael Henry Millett 11/5/1957 to 03/08/2012 Gone but will never be forgotten-RIP (Uncle Chuck)Charles Manning Gulbronsen Sr 1956-2012 Taken from us to soon but you will live on in our hearts-RIP

10-03-2007, 06:29 AM	#2
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 Best transfr case is a NP205 best axles would be Dana 60 front and 14blt rear. __________________ Earl 68 2500 4x4 GMC Burb

10-03-2007, 10:50 AM	#3
Burt4x4 Registered User Join Date: Feb 2000 Location: Modesto, CA Posts: 1,842	Re: Turning a C-20 into a K-20 Yup, get a 1Ton donor 4x4 and swap it in. __________________ 1972 K5 MPFI454/Sm465/Np205/D60/14FFd/Re-Centerd H1s w/Swamper Iroks

10-03-2007, 09:48 PM	#4
toomanytoyz Luv the Crewcabs Join Date: Aug 2006 Location: Andrews, In. 46702 Posts: 4,097	Re: Turning a C-20 into a K-20 If you are Intent on Doing this, I feel best Route would be to Find a Donar Frame & Swap Body Over. Much Easier than trying to add Axle's to your 2x4 Frame........... Good Luck, Rick

10-04-2007, 01:06 AM	#5
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 I think adding 4wd axles to the 2wd frame is easier then swaping bodys unless you are planing on doing a frame off resto any way. __________________ Earl 68 2500 4x4 GMC Burb Last edited by earl87gta; 10-04-2007 at 01:06 AM.

10-04-2007, 10:09 PM	#6
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 I converted a 1976 C30 from 2wd to 4wd and it was really simple. I took a 4" square tube 1/4" wall, measured and placed the spring hangers where a 4x4 trucks are. Then I did some measuring to find the axle center line and drilled a 5/8 hole in my tube and it so happened that there was already a hole in the frame so I bolted it down. Then I welded it to the frame to ensure it wasn't going anywhere. I did some more measuring and cut a hole in the rear part of the frame below the firewall for a 4x4 shackle. I went to my buddy's junk yard and got the cast shackle mount from a full time rusted out turd. I then made sure it was square and drilled four more holes and bolted it on using grade 8 bolts. I made the shackles from 1"x5/16" flat stock. I didn't make the shackles until I had the leaf springs on and the axle under it so I could get the truck level. I used 6" lift springs and with the 4" tube it is 10" of lift. I used a 4wd steering box and the rest is pretty easy from there. Oh one more thing, I did use the engine crossmember from the K20 as well because you will get rid of the 2wd one.

10-04-2007, 10:18 PM	#7
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 For the rear I used spring hangers from a 4x4 truck also because the 2wd ones were a lot shorter. I kept the 2wd leaf springs and did a shackle reversal on the rear and used a 4" lift block. My friend has a 1981 3/4 ton with a 10" lift and 36's and my truck sits about 1 1/2" taller than his. Here are some links to some pics. http://i191.photobucket.com/albums/z...s/100_0456.jpg http://i191.photobucket.com/albums/z...s/100_0453.jpg http://i191.photobucket.com/albums/z...s/100_0536.jpg I will try to find some pics of the front set up for ya.

10-05-2007, 03:25 PM	#8
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 do a serch ob b-52 or diy4x and they make every thing to do the convertion __________________ Earl 68 2500 4x4 GMC Burb

10-08-2007, 03:12 PM	#10
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 I think Im going to copy your Idea grendel but Im going to shorten the 1ton frame to work with my burb. __________________ Earl 68 2500 4x4 GMC Burb

10-09-2007, 01:15 AM	#12
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 Im going that route in case I do get a 6bt to put in the burb. Plus braging wrights to say I have the only true 100% 1 ton 68 burb __________________ Earl 68 2500 4x4 GMC Burb

10-09-2007, 03:19 AM	#13
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 If you need any info on swapping a 6bt in let me know, I have done many diesel conversions. I am currently working on a 1991 f350 with one.

10-09-2007, 03:44 AM	#14
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 Cool thanks I have a 6.2 I was going to put in it but Im watching for a 6bt at a good price to use instead. if I dont find one by the time Im ready for the engine the 6.2 will go in. __________________ Earl 68 2500 4x4 GMC Burb

10-09-2007, 03:49 AM	#15
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 Keep an eye on ebay I saw a 94 p pump engine probabally a 160hp unit with a nv4500 5 speed with a starting bid of 1500 and no one had bid on it as of then. That is a steal of a deal.

10-09-2007, 04:15 AM	#16
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 The cheapest one I found here was 3k with no trans. __________________ Earl 68 2500 4x4 GMC Burb

10-09-2007, 04:28 AM	#17
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 Here is an ebay link to one right now. It would be a good start. http://cgi.ebay.com/ebaymotors/5-9-C...QQcmdZViewItem



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10-09-2007, 04:35 AM	#18
Dieselwrencher 6>8 Plugless........ Join Date: Sep 2007 Location: Prairie City, Ia Posts: 17,142	Re: Turning a C-20 into a K-20 Here is another http://cgi.ebay.com/ebaymotors/CUMMI...QQcmdZViewItem

10-09-2007, 12:40 PM	#19
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: Turning a C-20 into a K-20 I bet shipping would be a lot of $$$$ 1974ChevyC10 sorry about the high jack. __________________ Earl 68 2500 4x4 GMC Burb Last edited by earl87gta; 10-09-2007 at 12:41 PM.

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