Pictures of your C10 tires - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**MikeB** · 03-27-2014, 10:17 PM

My "new to me" 82 SWB C10 has 6.5" Rally wheels (from a van?) and 255-70x15 tires that are nearly shot. The glove box sticker shows the truck originally came with FR78x15 tires, which are equivalent to 205-75x15. That sounds really small, but I know my 250 six would like their shorter height with the lame 2.73 axle, and my speedometer would be more accurate.

I'd appreciate pictures of trucks with 205-75, 215-75. and even 225-75 tires, if anyone has 'em. Also, what the heck, 235-70x15.

**brakenit** · 03-28-2014, 04:20 AM

Pretty sure my '84 was still sporting the stock size 205/75/15's when I got it.

D13 · 03-28-2014, 06:14 AM

Mine are P235 75R15's, I can't imagine anything smaller withstanding the weight of my 6.2 diesel, or a BBC. That's on standard truck ralley's.

Keith Seymore · 03-28-2014, 07:22 AM

Base tires are really pretty small, because any money you can save per tire is multiplied by at least 4 (some trucks did not get a spare) or 5.

Here's mine with P235/75R15s on a 15x8 rally.

K

**MikeB** · 03-28-2014, 08:43 AM

Thanks, guys. Keep 'em coming. Yeah, the 205s look awfully small in those big wheel wells!

I've had a few trucks over the years that ran 235-75x15, which has always been a popular size to run on pickups with 15" wheels. In fact, I initially thought I'd buy 235s, but then realized my axle is a 2.73, and wheel width is only 6.5".

Keith, what the heck was GM thinking when they made 2.73 the "standard" ratio for a 6-cylinder, manual trans pickup? The 3.50 1st gear makes it easy to get the truck rolling, but the gaps between gears is just nuts. Then again, my current 255-70 tires are 2" taller than a 205-75, which makes the 2.73 seem like 2.54.

**old Rusty C10** · 03-28-2014, 08:49 AM

my truck has 225 75 R 15 tires on it pics while it was still a project

Keith Seymore · 03-28-2014, 11:32 AM

Quote:

Originally Posted by MikeB

Keith, what the heck was GM thinking when they made 2.73 the "standard" ratio for a 6-cylinder, manual trans pickup? The 3.50 1st gear makes it easy to get the truck rolling, but the gaps between gears is just nuts. Then again, my current 255-70 tires are 2" taller than a 205-75, which makes the 2.73 seem like 2.54.

Fuel economy!

I always start at 3.42 and then move from there when choosing an axle ratio. 3.42 and 3.73 pretty much cover all my needs.

K

**MikeB** · 03-28-2014, 05:26 PM

Quote:

Originally Posted by Keith Seymore

Fuel economy!

I always start at 3.42 and then move from there when choosing an axle ratio. 3.42 and 3.73 pretty much cover all my needs.

K

I didn't know CAFE standards applied to light trucks.

Yeah, my little 250 six would probably like 3.73, but not on the highway! I'm thinking shorter tires for the time being, and maybe 3.23-3.42 gears if I keep the six. I've done R+P swaps on two 10-bolts and one 12-bolt, so I'm armed and dangerous!

Back in the late 80s I had an 81 C-10 with 305, TH350C, and 2.56 axle (!). If the T/C locked up at speeds less than 40-45 mph, the entire truck would shudder. Drove it around in 2nd gear a lot, until I installed an under-dash switch to control the lock-up. And I only engaged the switch when driving at highway speeds.

walkerb · 03-28-2014, 10:48 AM

235 75 15

geezer#99 · 03-28-2014, 10:53 AM

225 70 front and 235 75 rear. Originals where 205 75's.

03-27-2014, 10:17 PM	#1
MikeB Senior Member Join Date: Jul 2000 Location: North Texas Posts: 3,597	Pictures of your C10 tires My "new to me" 82 SWB C10 has 6.5" Rally wheels (from a van?) and 255-70x15 tires that are nearly shot. The glove box sticker shows the truck originally came with FR78x15 tires, which are equivalent to 205-75x15. That sounds really small, but I know my 250 six would like their shorter height with the lame 2.73 axle, and my speedometer would be more accurate. I'd appreciate pictures of trucks with 205-75, 215-75. and even 225-75 tires, if anyone has 'em. Also, what the heck, 235-70x15. __________________ Mike 1969 C10 LWB -- owned for 35 years. 350/TH350, 3.08 posi, 1st Gen Vintage Air, recent AAW wiring harness, 5-lug conversion, 1985 spindles and brakes. 1982 C10 SWB -- sold 1981 C10 Silverado LWB -- sold, but wish I still had it! 1969 C10 (not the current one) that I bought in the early 1980s. Paid $1200; sold for $1500 a few years later. Just a hint at the appreciation that was coming. Retired as a factory automation products salesman. Worked part-time over the years for an engine builder and a classic car repair shop. Member here for 24 years! This is the very first car/truck Internet forum I joined. I still used a dial-up modem back then! Last edited by MikeB; 03-27-2014 at 10:43 PM.

03-28-2014, 04:20 AM	#2
brakenit Active Member Join Date: Mar 2004 Location: Indiana Posts: 198	Re: Pictures of your C10 tires Pretty sure my '84 was still sporting the stock size 205/75/15's when I got it.

03-28-2014, 06:14 AM	#3
D13 Registered User Join Date: Feb 2007 Location: Memphis MI Posts: 1,851	Re: Pictures of your C10 tires Mine are P235 75R15's, I can't imagine anything smaller withstanding the weight of my 6.2 diesel, or a BBC. That's on standard truck ralley's. __________________ 1987 2 ton 1982 250/TH350 beater in progress Dad's 1981 3/4 L6 3 on tree posi and no options, awaiting restoration or scrapping Plus a mess o' tractors

03-28-2014, 07:22 AM	#4
Keith Seymore Registered User Join Date: May 2009 Location: Motor City Posts: 9,226	Re: Pictures of your C10 tires Base tires are really pretty small, because any money you can save per tire is multiplied by at least 4 (some trucks did not get a spare) or 5. Here's mine with P235/75R15s on a 15x8 rally. K __________________ Chevrolet Flint Assembly 1979-1986 GM Full Size Truck Engineering 1986 - 2019 Intro from an Old Assembly Guy: http://67-72chevytrucks.com/vboard/s...d.php?t=342926 My Pontiac story: http://forums.maxperformanceinc.com/...d.php?t=560524 Chevelle intro: http://www.superchevy.com/features/s...hevy-chevelle/

03-28-2014, 08:43 AM	#5
MikeB Senior Member Join Date: Jul 2000 Location: North Texas Posts: 3,597	Re: Pictures of your C10 tires Thanks, guys. Keep 'em coming. Yeah, the 205s look awfully small in those big wheel wells! I've had a few trucks over the years that ran 235-75x15, which has always been a popular size to run on pickups with 15" wheels. In fact, I initially thought I'd buy 235s, but then realized my axle is a 2.73, and wheel width is only 6.5". Keith, what the heck was GM thinking when they made 2.73 the "standard" ratio for a 6-cylinder, manual trans pickup? The 3.50 1st gear makes it easy to get the truck rolling, but the gaps between gears is just nuts. Then again, my current 255-70 tires are 2" taller than a 205-75, which makes the 2.73 seem like 2.54. __________________ Mike 1969 C10 LWB -- owned for 35 years. 350/TH350, 3.08 posi, 1st Gen Vintage Air, recent AAW wiring harness, 5-lug conversion, 1985 spindles and brakes. 1982 C10 SWB -- sold 1981 C10 Silverado LWB -- sold, but wish I still had it! 1969 C10 (not the current one) that I bought in the early 1980s. Paid $1200; sold for $1500 a few years later. Just a hint at the appreciation that was coming. Retired as a factory automation products salesman. Worked part-time over the years for an engine builder and a classic car repair shop. Member here for 24 years! This is the very first car/truck Internet forum I joined. I still used a dial-up modem back then! Last edited by MikeB; 03-28-2014 at 08:48 AM.

03-28-2014, 08:49 AM	#6
old Rusty C10 Robert Olson Transport Join Date: Oct 2002 Location: recent transplant to NC USA Posts: 20,310	Re: Pictures of your C10 tires my truck has 225 75 R 15 tires on it pics while it was still a project Attached Images __________________ Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!!

03-28-2014, 10:48 AM	#9
walkerb Registered User Join Date: May 2010 Location: Rochester NY Posts: 831	Re: Pictures of your C10 tires 235 75 15 Attached Images __________________ 1973 k20 Suburban 350 1974 Custom stepside c-10 250 1975 Chevy stepside 454 1986 K30 Crewcab SRW 350 R.I.P- glimmertwin01- board member and good friend, you will be missed

03-28-2014, 10:53 AM	#10
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,731	Re: Pictures of your C10 tires 225 70 front and 235 75 rear. Originals where 205 75's. Attached Images



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.