[SSSIERA]

what are the standard tyres size for a sierra

[Fatzook]

205/70 15

[Choppy]

not sure but 26" i think

edit: beaten

[Gwagensteve]

H7815 for JX NT's

6.00X16 for "commercial" 1.3's and 1.0 litres.

205/70/15 for WT's (mid 1988 onwards)

Maruti's stuck with H7815 AFAIK.

Steve.

[SSSIERA]

cheers

edit: all of you

[SSSIERA]

without gearing what should i put on my sierra, i wanna go as big as possible without any gear box probs is 30s pushing it

[Fatzook]

You won't have any gearbox probs. You'll just get sick of changing gears everytime there is a 1 degree incline or someone in the car infront farts, causing the resulting flatulant wind to slow your vehicle.

No bigger than 30's would be my vote.

[Gwagensteve]

30's is borderline depending on the terrain you drive.

Steve.

[S13RR4]

I noticed 29's with my 1.3L

Choppy didn't as much with his 1.6L

I have 1lt transfer case now and its much better

[alien]

215/75r15 if you want to keep a usable low range... if you're driving sand a 235 would be "get-away-with-able" in my opinion.

dont forget a 215/75r15 is 6.5% larger than factory... so when the speedo reads 100km/hr you're really doing 106.6 etc... same affects your lower down speeds... where right now you might do say 1000 rpm in 1st gear, crawling along... rev it to around 1100rpm and imagine that being the slowest you can go.

there comes a point where you're just going too fast to be controlled going over things and end up riding the clutch all day to keep it slow.

[ando_zook94]

I got 30's with the standard 1.3 n gearing.
Hills r not your friend:/
Ended up in 2nd on the highway haha

[SierraDan]

Geez.. I've got 31's and just barely had to drop back to 3rd up a hill.
But agree that it's crap without gearing mods. I wouldn't go up from 235's without gearing.

[dawsey]

Ive got 235 on mine .untouched gears.I can notice it but still very drivable on the highway and low range..wouldnt go any bigger..after awhile you forget what stockos drive like anyway.

[Moph]

I had 235/75R15's on mine with stock gearing ... fine on the highway (better even) but not great offroad. Burnt way too much clutch saving the rest of the driveline.

[SSSIERA]

i dont realy care if i have to piss other drivers of by going slow, but i do care if ima need a new clutch. sigh i was thinking 28s but i wanna go bigger

[SSSIERA]

recon the small tyres r gona look shite with a 4 inch lift

[Fatzook]

SSSIERA wrote:

recon the small tyres r gona look shite with a 4 inch lift

Yep!

[SierraDan]

Yeah that's a given. Stock tyres look crap on a TWO inch lift.

[bohuler]

My lwb has 215, 75, 15's and thats whats one the tire placard so i thought it was standard. Mine is an 85 n/t lwb and its also the smallest bfg will do a km2 muddy altho you can't get the buggers atm.
Dave

[Gwagensteve]

bohuler wrote:

My lwb has 215, 75, 15's and thats whats one the tire placard so i thought it was standard. Mine is an 85 n/t lwb and its also the smallest bfg will do a km2 muddy altho you can't get the buggers atm.
Dave

I don't believe you. I have an 86 N/T LWB and it's H 78 15.

Personally, I think 215 is too small to spend money on. A 235 is a much better option.

Steve.

[bohuler]

ok i stand corrected. i would of sworn that they said 215 :p So can you explain why the fu&*k don't they have the tyre size. WTF does FR 78-15 mean?


Could someone explain the number here?

Dave

[303zuke]

Gwagensteve wrote:

bohuler wrote:

My lwb has 215, 75, 15's and thats whats one the tire placard so i thought it was standard. Mine is an 85 n/t lwb and its also the smallest bfg will do a km2 muddy altho you can't get the buggers atm.
Dave

I don't believe you. I have an 86 N/T LWB and it's H 78 15.

Steve.

Can we see a pic of the H78 15 placard? I've always thought the JX NT's were FR78 Bridgestones?

[303zuke]

bohuler wrote:

So can you explain why the fu&*k don't they have the tyre size. WTF does FR 78-15 mean?

Could someone explain the number here?

Dave

FR78 15 is an older tyre size, but not as old as the 6.00-16 style sizing. The 78 means it is a 78% aspect ratio tyre, while sizes A, B, C etc get bigger. The R means it's a radial tyre. 15 is for a 15" rim. A FR78 15 is approximately equivalent to a 205/75-15. Note that the widetracks had a 205/70-15 tyre, which is lower profile than a FR78 and smaller diameter, which is why they changed from 3.9 diffs to 3.7.

6.00-16 is a 100% aspect ratio tyre that nominally is 6 inches in section width and 6 inches in height (although they are rarely exactly these dimensions) for a 16" rim.

[remydog05]

Gwagensteve wrote:

H7815 for JX NT's

6.00X16 for "commercial" 1.3's and 1.0 litres.

205/70/15 for WT's (mid 1988 onwards)

Maruti's stuck with H7815 AFAIK.

Steve.

So going by this the NT 1.3 was known as a commercial?

What measurement in our current sizes do these compare too?
EG a 30/9.5 or 29?? 31??

[303zuke]

There were 2 spec levels for the NT Sierras, JA and JX.

JA was the commercial or basic version and had 6.00-16 bar tread tyres. The body had no flares, there was no Tacho or dash clock, vinyl floor mats and low-back seats.

JX had FR78-15 tyres, small rubber flares, Tacho and clock, carpets and cloth seats in Hard-top, full-floor mats in soft-top and better vinyl sears with headrests.

1.0 JA soft-tops had half doors (like Drover). Hi-roof was only available as JX

205/75-15 = 670mm = 26.4in.

FR78-15 = 690mm = 27.1in.

6.00-16 = 725mm = 28.1in.

[alien]

http://www.turbinecar.com/tires.htm

has a good chart.

the 6.00-16 is what most people use to argue engineering a larger tyre size too, cos going from a 28 to a 31 is only a 10.7% increase rather than the 19.2% increase over a 205/70r15.

[Gwagensteve]

303zuke wrote:

Can we see a pic of the H78 15 placard? I've always thought the JX NT's were FR78 Bridgestones?

My bad - F78 not H78.

Steve.

[SSSIERA]

TO MANY DIFFERENT NUMBERS

[TZAR]

303zuke wrote:

bohuler wrote:

So can you explain why the fu&*k don't they have the tyre size. WTF does FR 78-15 mean?

Could someone explain the number here?

Dave

FR78 15 is an older tyre size, but not as old as the 6.00-16 style sizing. The 78 means it is a 78% aspect ratio tyre, while sizes A, B, C etc get bigger. The R means it's a radial tyre. 15 is for a 15" rim. A FR78 15 is approximately equivalent to a [url=http://tireguides.com/print_friendly2.asp?.

The alpha numeric size tyres where about load ratings. The letter dictated how much load a tyre could carry. Stupid american attempt at sizing. Wish they would just get with the metric system....

[atari4x4]

Gwagensteve wrote:

bohuler wrote:

My lwb has 215, 75, 15's and thats whats one the tire placard so i thought it was standard. Mine is an 85 n/t lwb and its also the smallest bfg will do a km2 muddy altho you can't get the buggers atm.
Dave

I don't believe you. I have an 86 N/T LWB and it's H 78 15.

Personally, I think 215 is too small to spend money on. A 235 is a much better option.

Steve.

don't believe tyre placards, they are adjustable...