Best susp lift for 72 K20 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

amstaff · 06-06-2003, 12:57 AM

I will be getting my hands on a 72 Chevy K20, and would like to run 33X10.50's. What is the minimum I will need to lift... 2"? I don't want this lifted too much. Also, what manufacturer(s) make a good kit, and who should I stay away from?
Thanks,
Amstaff

jeffspower · 06-06-2003, 02:39 AM

They should clear ok with no lift. 10.50's with the proper wheel should clear fine, unless your front springs are saggy. 12.50's would be a little too tight. I had 255/85/16 mud T/A's on my '72 K-20 at first. 4" lift put plenty of daylight in the wells. I run 38/13.00/16 TSL's with about 5" suspension & 3" body. They just barely touch the backside of the front fenders when wheelin' hard. My front springs are from a '60 IH one ton & are pretty stiff. They sit on a 2" block- I know, you are not supposed to do this but it is solid as can be. If Marmon-Herrington does it on everything from one tons to 6x6 trucks weighing 25+ tons, ambulances, school buses, fire trucks- I don't see a problem when done right. Mine drives pretty good. But, if I would have had some cash in my pocket, I probably would have just bought a kit.

**JIMs70GMC** · 06-06-2003, 01:11 PM

I have 33x12.5 w/ 2" lift. If you keep those tires on 8" rims w/ abou3-4" of backspacing they'll probably never rub. My 2" springs are from tuff country, ride real good. The skyjacker softrides are supposedly really good also. I'd say stay away form Rancho their spring rate is above 500 lb/in. jeff, I believe in those heavy/medium duty applications there is a bolt running through the block not just u-bolts holding it there. ORD and some others sell what's called a zero-rate add-a-leaf that bolts to the spring pack.

1967K10 · 06-17-2003, 01:21 PM

I don't have a 72, but I have been doing research for my 67 and have heard several times that Skyjacker and Tough Country have some of the better riding systems out there. (I've still got a few websites saved in my "favorites" for these systems, let me know if you want 'em) I've never lifted one before, so take what I say with a grain of salt.

What is the end use of your truck going to be? Daily driver or off road?

amstaff · 06-17-2003, 04:46 PM

It is going to be my daily driver and will not see much, if any, time off of the highway. It also will serve as our plow truck.
Please forward the websites for the lifts... I have already been in touch w/ Tough Country and now I would like to see what else is out there (in a 2").
Thanks,
Amstaff

1967K10 · 06-17-2003, 09:22 PM

http://www.offroaddesign.com/ is for a small company I have heard lots of great things about that deals in Tough Country lifts.

http://www.4wheelparts.com/product2....RJ9PAD38DCBG3B sells skyjacker kits.

2wdBlazer · 06-19-2003, 01:48 PM

I Ran 33x12.50's on my last Blazer and the fit with no rubbing on stock suspention.

smokekiki · 06-19-2003, 03:59 PM

I have tough country e-z ride springs,front and rear,4"lift with 35's.I am pleased with the ride on my blazer.

amstaff · 06-19-2003, 05:53 PM

Has anyone ever run 35X12.50's on a K20? I wonder if they would clear with a 2" suspension lift with no off road use.

**JIMs70GMC** · 06-20-2003, 05:45 AM

Not all 35s are created equal. I'm sure you could find 35s that only measure 33"-34". Check the manufatures web sites. My 33s are actually a hair under 34". Also seen where the pro-comp 33s are actually under 32" tall. So you can have 35s and still get away with smaller lift. I have a skyjacker lift article that they say you need 6" of lift to clear 35s but if you seen the flexing they were doing you'd know why I'll post the link when I get home this evening.

Pont · 06-28-2003, 03:09 PM

As Jims70 stated in a earlier post, it's hard to say that a certain size tire will work with a certain size lift. Other factors are involved. For example, many poeple say that you can run 35's with a 4" lift and not rub but I am running 35's with an 8" lift and my front tires still rub from time to time. It's because I am run a 14.5" wide tire on a 14" wide rim with only 3 5/8" backspacing. So you really need to look at how wide of a tire you run and how wide of a wheel they are mounted on and how much you want that combo to stick out based on how much (or little) backspacing you have. Just choose your sizes carefully so you haven't wasted money on the wrong lift or wheel and tire size.

Personally, I think 33x10.5 tires on a 8" rim with a 2" lift would look good. If you think you might wanna go wider or taller than that, go with a 4" lift. A 4" lift is not that tall, I recently put a 4" lift on my dads 84 K10 and he's almost 60 years old. No problem getting in and out of a truck with a 4" lift.

Good luck, keep us posted on what you go with. Pics would be nice too!

Rob

wildwood · 07-04-2003, 10:38 AM

On my '70 GMC I had 33x9.5 BFG TA on 8" rims with saggy stock suspension with no rubbing. When I put 33x12.5 BGF TA on 10" rims, I had to put on 2.5" 3/4 ton springs, I used Skyjacker softrides (great springs) up front and Rancho add-a leaf and a 1.5" block in the rear with no rubbing. This is also a very inexpensive way to lift the truck. When you do a 2.5" suspension lift, you can use the stock brake lines, shocks etc. Now I'm running 35x12.5 Kelly MTs , I did a 2" body lift, again no rubbing even off-road I think I might even try to fit some 36x12.5 Swapmers when I go for some new rubber, I'll have to eye it up first.

Good luck with your lift!

06-06-2003, 12:57 AM	#1
amstaff Registered User Join Date: Oct 2002 Location: State College, PA Posts: 178	Best susp lift for 72 K20 I will be getting my hands on a 72 Chevy K20, and would like to run 33X10.50's. What is the minimum I will need to lift... 2"? I don't want this lifted too much. Also, what manufacturer(s) make a good kit, and who should I stay away from? Thanks, Amstaff

06-06-2003, 01:11 PM	#3
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	I have 33x12.5 w/ 2" lift. If you keep those tires on 8" rims w/ abou3-4" of backspacing they'll probably never rub. My 2" springs are from tuff country, ride real good. The skyjacker softrides are supposedly really good also. I'd say stay away form Rancho their spring rate is above 500 lb/in. jeff, I believe in those heavy/medium duty applications there is a bolt running through the block not just u-bolts holding it there. ORD and some others sell what's called a zero-rate add-a-leaf that bolts to the spring pack. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

06-17-2003, 01:21 PM	#4
1967K10 Registered User Join Date: Jan 2003 Posts: 32	I don't have a 72, but I have been doing research for my 67 and have heard several times that Skyjacker and Tough Country have some of the better riding systems out there. (I've still got a few websites saved in my "favorites" for these systems, let me know if you want 'em) I've never lifted one before, so take what I say with a grain of salt. What is the end use of your truck going to be? Daily driver or off road? Last edited by 1967K10; 06-17-2003 at 01:24 PM.

06-19-2003, 01:48 PM	#7
2wdBlazer The Blazer King Join Date: Sep 2000 Location: Valrico, Fl (Tampa) Posts: 1,213	I Ran 33x12.50's on my last Blazer and the fit with no rubbing on stock suspention. __________________ 72 2wd Blazer. Its the superbichinest, megacoolinest, superflowinest.

06-19-2003, 03:59 PM	#8
smokekiki Mike Join Date: Jan 2003 Location: west chester pa Posts: 2,474	I have tough country e-z ride springs,front and rear,4"lift with 35's.I am pleased with the ride on my blazer. __________________ 70'c/10, 71 suburban4x4 402bb, 72suburban 4/6 drop, 72k/5 4x4 blazer 4" lift 35 tires

06-06-2003, 02:39 AM	#2
jeffspower Well, Whoop-dee-do! Join Date: Mar 2003 Location: Easton, Mo. pop.- me & scarcely a few others Posts: 2,302	They should clear ok with no lift. 10.50's with the proper wheel should clear fine, unless your front springs are saggy. 12.50's would be a little too tight. I had 255/85/16 mud T/A's on my '72 K-20 at first. 4" lift put plenty of daylight in the wells. I run 38/13.00/16 TSL's with about 5" suspension & 3" body. They just barely touch the backside of the front fenders when wheelin' hard. My front springs are from a '60 IH one ton & are pretty stiff. They sit on a 2" block- I know, you are not supposed to do this but it is solid as can be. If Marmon-Herrington does it on everything from one tons to 6x6 trucks weighing 25+ tons, ambulances, school buses, fire trucks- I don't see a problem when done right. Mine drives pretty good. But, if I would have had some cash in my pocket, I probably would have just bought a kit.

06-17-2003, 04:46 PM	#5
amstaff Registered User Join Date: Oct 2002 Location: State College, PA Posts: 178	It is going to be my daily driver and will not see much, if any, time off of the highway. It also will serve as our plow truck. Please forward the websites for the lifts... I have already been in touch w/ Tough Country and now I would like to see what else is out there (in a 2"). Thanks, Amstaff

06-17-2003, 09:22 PM	#6
1967K10 Registered User Join Date: Jan 2003 Posts: 32	http://www.offroaddesign.com/ is for a small company I have heard lots of great things about that deals in Tough Country lifts. http://www.4wheelparts.com/product2....RJ9PAD38DCBG3B sells skyjacker kits.

06-19-2003, 05:53 PM	#9
amstaff Registered User Join Date: Oct 2002 Location: State College, PA Posts: 178	Has anyone ever run 35X12.50's on a K20? I wonder if they would clear with a 2" suspension lift with no off road use.

06-20-2003, 05:45 AM	#10
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	Not all 35s are created equal. I'm sure you could find 35s that only measure 33"-34". Check the manufatures web sites. My 33s are actually a hair under 34". Also seen where the pro-comp 33s are actually under 32" tall. So you can have 35s and still get away with smaller lift. I have a skyjacker lift article that they say you need 6" of lift to clear 35s but if you seen the flexing they were doing you'd know why I'll post the link when I get home this evening. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

06-28-2003, 03:09 PM	#11
Pont I need another Barley Pop Join Date: Feb 2001 Location: Grants Pass, OR Posts: 1,629	As Jims70 stated in a earlier post, it's hard to say that a certain size tire will work with a certain size lift. Other factors are involved. For example, many poeple say that you can run 35's with a 4" lift and not rub but I am running 35's with an 8" lift and my front tires still rub from time to time. It's because I am run a 14.5" wide tire on a 14" wide rim with only 3 5/8" backspacing. So you really need to look at how wide of a tire you run and how wide of a wheel they are mounted on and how much you want that combo to stick out based on how much (or little) backspacing you have. Just choose your sizes carefully so you haven't wasted money on the wrong lift or wheel and tire size. Personally, I think 33x10.5 tires on a 8" rim with a 2" lift would look good. If you think you might wanna go wider or taller than that, go with a 4" lift. A 4" lift is not that tall, I recently put a 4" lift on my dads 84 K10 and he's almost 60 years old. No problem getting in and out of a truck with a 4" lift. Good luck, keep us posted on what you go with. Pics would be nice too! Rob __________________ 67 Short Fleet 4x4 04 Honda CRF450R 89 Toyota 4-Runner 34 Ford 2 door sedan - Long term project ---------------------------------------------- There is a very fine line between "hobby" and "mental illness"

07-04-2003, 10:38 AM	#12
wildwood Registered User Join Date: Jun 2003 Location: Calgary AB Posts: 110	On my '70 GMC I had 33x9.5 BFG TA on 8" rims with saggy stock suspension with no rubbing. When I put 33x12.5 BGF TA on 10" rims, I had to put on 2.5" 3/4 ton springs, I used Skyjacker softrides (great springs) up front and Rancho add-a leaf and a 1.5" block in the rear with no rubbing. This is also a very inexpensive way to lift the truck. When you do a 2.5" suspension lift, you can use the stock brake lines, shocks etc. Now I'm running 35x12.5 Kelly MTs , I did a 2" body lift, again no rubbing even off-road I think I might even try to fit some 36x12.5 Swapmers when I go for some new rubber, I'll have to eye it up first. Good luck with your lift! __________________ You can't get out if ya don't get in



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