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Gettin' Old

bigcitybrianwright

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Anybody know if 33s will fit under a standard factory suspension in a 89 Jimmy (or K5)?

I've been runnin' 35 BFGs for along time with a 6" Rough Country suspension lift. It rides like **** and is too loud to listen to music at a comfortable level or talk on the phone. I guess I'm getting old, but I just want a better ride with a good look. So, I'm thinking 33 Wrangler MT/R w/ Kevlar and back to standard lift.
 
Seems like alot of people have no prob and some do. I think it depends on the actual measurement of the tires. My 32s Really measure 31. Ive seen alot of 33s brand new actually measure 32. I know my buddies trxus mts that measure 33 barely fit and i couldnt turn AT ALL.
 
That has more to do with tread pattern than tire size, especiially only a 2" size difference.
 
Tire width (Pythagorean theorem) and wheel spacing are the issues with 33's IMO.

Buddy is running 33x12.5's on stock wheels, and rubs.

I'm running 33x10.5's on stock wheels, with old, worn out springs, and it never rubs.
 
That's also a width issue with that. I have same thing, I run 39.5x18s and my buddy has 39.5x15 and I rub and he doesn't. With same basic lift. BFGs MTs are a louder tire, especially as they wear. Maybe look into a more street tire pattern, I'm fond of their ATs, no not a "mud" tire, but a decent all around that lasts
 
Thats what I was talking about with the Pythagorean Theorem. And I hate math. :)

I drew up a diagram. Not sure if non-members can see the attachment or not, if not, apologies. It's the pythagorean theorem used on a tire. It's fairly rough as it assumes the tire specs are "as advertised".

While the "X" difference is fairly small (under 1") as in the case with 33" tires and stock suspension, it is obviously enough of a difference to potentially contribute or cause an issue with tire rub, or in the case of my buddies truck and mine, it IS the issue. As you can tell (obviously), that comes into play when the tire is turned.

Simple answer? Narrower tire with same diameter is less likely to rub, but that is no guarantee. Too many variables.

tire.jpg
 
You have quite possibly gave me high school nightmares again with your fancy math terms. Haha, man I don't miss all that. But yes, your observation is correct, and I was going to use it, but that word wasn't in my auto correct on that thur smart phone. And I didn't feel like tryin to look smart, but spelling it wrong. What I learned was, when in doubt, sawzall it out, or use more throttle.
 
Anybody know if 33s will fit under a standard factory suspension in a 89 Jimmy (or K5)?

I've been runnin' 35 BFGs for along time with a 6" Rough Country suspension lift. It rides like **** and is too loud to listen to music at a comfortable level or talk on the phone. I guess I'm getting old, but I just want a better ride with a good look. So, I'm thinking 33 Wrangler MT/R w/ Kevlar and back to standard lift.



before you give up on the lift, try some softer springs (Tuff Country)

I've always heard the Rough Country are just that - rough!
 
I had the factory heavy half and could clear 33's. That uses the 3 leaf front springs. Never really wheeled it hard like that tho. My 4 inch front rancho springs just busted a bottom spring so I removed the bottom spring out of each Pac and installed an ez inch(zero rate) in there place. Rides alot softer.
 
go with the 33's and a set of 2" or 3" alcans. you'll be happy as can be:thumb:
 
Yeah, Rough Country lives up to it's name. There's lots better riding lift springs out there, even before you go the custom spring route.

That said yes, 33's will fit...MAYBE.

I had 305/70R16 (33x12.5R16) muds on 16x8's with 4" of backspacing on my stock '89 K5. Despite 200k saggy springs (the rear even sat 1" lower on one side) and the heavy diesel engine in the front they fit with only minor rubbing of the front fang of the fender while turning with compression up front. Driving down the road and turning without compression of the front suspension they never rubbed.

If you run a stock type wheel spec and don't go crazy on the tire it should be doable. Too wide of a rim or low backspacing and you could get even 31's to rub.

Also if the stock springs were completely sagged out you'd be in trouble due to that. This can play a major factor. Mine JUST fit but I met a guy with a '89 K5 that had 60,000 original miles on it. He could just about clear 35's under his. It looked like his truck was lifted compared to mine.
 
I have a 2.5 inch lift on my Burb and run 33 inch Goodyear Duratracs on the factory 8 inch rims, no clearence issues at all. Be sure to budget for shocks in the lift equation, you will need to change those too.
 
Ive got 33in Goodyear MTR's on my M1009, and have never had them rub, even with light wheeling. Totally stock suspension with front springs worn so bad they bend the wrong way. :whistle:
 
Ive got 33in Goodyear MTR's on my M1009, and have never had them rub, even with light wheeling. Totally stock suspension with front springs worn so bad they bend the wrong way. :whistle:

So they bend upwards then like the rears? :screwy:
 
So they bend upwards then like the rears? :screwy:

nope... the front springs are bent like the letter "n", the springs on the rear are shaped like the letter "u".... I was told that was worn springs that bent the wrong way..... :whistle:

Made sense because every lift kit ive ever seen or new springs, or springs on other trucks all looked like "u"s.

so what your saying is springs that look like "n u" are normal?

and they only look like "U U" after they've been lifted?
 
Yep. My 89 from the factory had negative arched springs in the front and positive arched in the rear.
And I was running 33x12s with factory springs with minor rubbing at full turn and some flexing. Just had to trim the inner fender lip but it wasn't even noticeable
 
I have a 3 pack of front springs on my Suburban with a 1" zero rate on the front, and stock half ton rear springs with a 2" lift block on the rear with a 1" body lift and people think I have a lot more lift than I really do.

Have you contemplated a 1" body lift?

Martin
 
You are going to need new springs anyhow so why not get some
Soft Alcans? They can make them Any rate you want because they're custom. I think ord makes the spring packs for each individual app from alcan spring specs
 

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