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Old 03-31-2015, 06:57 PM   #1
Burbnasty
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86 Suburban Lift and gearing questions

Hey
New to the forum, not to the 73-91s or to the 67-72 trucks and mostly burbs. I have been reading posts from the forum for along time, but just signed up. Among many things I have an 86 suburban, that I have had for several years, it is pretty solid especially for an 86 that has spent its entire life in Michigan. (i park him in the winter) My family and I use this for a weekend cruiser, trail rig, pull jetskis to the lake, camping ect. It needs some tlc, that I have not done for a while because I have had my eyes peeled for an 87-91 4x4 burb 2500 with the throttle body or, another 4x4 67-72, or a super clean 70-s 4x4 with the woodgrain interior that I like . I kind of always planned on selling this one to fund the purchase of one of the three listed above. I really have had no luck in finding something as solid as I would like in my price range so I guess its kind of time to commit to the 86 (which is fine, it a great rig that has treated me well)

The 86 is a half ton, it has stock suspension 3.42 gears and no posi.
It absolutely needs before summer:
-New tires
-If I'm doing new tires I would like to step up to a 35s or I would settle for 33s
- A new carb, it has run so well for so long that I have left all emissions in tact, but I can no longer tune and re tune the stupid Q-jet.
I have several other things on the list but for now this is on top.

My questions.

Can I go to a 4 inch lift and the 35s with the 3.42 gears?
I don't do lots of freeway driving but I am on the highway alot.

I have searched high and low, on what lift to buy. I have heard everything from "don't buy rough country", to "rough country has changed and it the best". The more I search the more overwhelmed I become.

Can anyone recommend a good 4 inch lift that isn't going to rattle me off the road?????

If the truck starts to ride like a tractor, my wife wont ride in it for too long, then the party's over!!!!!

I have two square body parts vehicles, an 89 blazer 4x4 and a 90 2500 two wheel peel burb. I could rob the throttle body off of one of those as apposed to buying a new $400 carb, but I read through some posts and it seems easier to just get the carb.
More looking for suggestions on the lift kit but if anyone has any input on the tbi swap, I have all parts and I'm all ears.

Thanks you guys
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Old 04-03-2015, 12:25 PM   #2
68Timber
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Re: 86 Suburban Lift and gearing questions

Burbnasty - sorry for the late reply and welcome to the forum. The lift recommendation is pretty easy, Tuff Country's EZ-Ride lifts get pretty much universal praise and they're priced right too. The gearing is a little more subjective. You can run 3.42's with 35's, I'm running 33's with stock 3.08 gears now on my 85. Mine doesn't have overdrive though, and you'd probably kill your 700R4 pretty quick if you tried going down hwy in OD at any speed that had it gear-hunting constantly. 4.11 gears would bring the rpms up to 1933 at 70 mph, but that might be a tad too little engine speed for a stock motor trying to push a lifted square through the breeze. 4.56 gears would bring the rpms up to 2145 at 70 mph, that'd be about perfect. On the flip side, if you keep your stock gearing, rpms at 70 would be right at 2300 if you had the transmission in drive instead of overdrive. I'd opt for the 4.56 gears, it'll perform better all around.
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Old 04-04-2015, 09:59 AM   #3
Burbnasty
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Re: 86 Suburban Lift and gearing questions

BRUISER, thanks for the info. In my parts 2wd burb I have a 14 bolt rear 4.11 axle with the stock g80 locker in it, I also salvaged from the junk yard a 4.56 rear axle with a Detroit locker out of a wrecked CUCV, (the front had already been grabbed). My truck is currently a half ton, both parts axles I have are 8 lug and I was going to try to save one of them for a different project. So it would probably be easier to just find another front 8 lug axle with the matching gears in it if I go this route.

The old burb has been able to handle all of its Upper Peninsular long distance trips, local camping, towing, and mild off roading duties up to this point, I use it almost every weekend in the spring, summer and fall.

How much drivability will I loose with the 4.56 or 4.11 gears, Mpg's, ect?

Should I just get new 32s and drive it as is?

If I do decide to run the 4.56 gears will my stock 700r4 keep up with the duties of those axles, and the 35s or am I asking for trouble?
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Old 04-04-2015, 10:17 AM   #4
xRAY76
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Re: 86 Suburban Lift and gearing questions

i think you might curl the front fenders with a 4'' w/35s
i had a 6'' w/ 35s and it took a really hard bounce to finally curl one.

its going to ride like a tank nomatter what lift you put on it, thats just the joy of owning a suburban/schoolbus
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Old 04-04-2015, 07:57 PM   #5
68Timber
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Re: 86 Suburban Lift and gearing questions

You'll lose some hwy mpg just for putting the box further up in the breeze, but I wouldn't expect a drastic drop. The 4.56 gears will actually help the 700R4 by giving it more mechanical advantage over the bigger tires, the gears will help the tranny not hurt. As far as drivability, hard to say. I like the way mine drives with a mild lift and tire upgrade but I'm sure it doesn't handle as well as a stock truck.

There's a lot to be said for putting new 31" or 32" tires on the truck and leaving it alone. If you still have the stock 15x8" rally wheels, supposedly you can mount 33's on those and they won't rub. I haven't done that myself but a few here have and say it works fine.
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Old 04-06-2015, 04:46 PM   #6
crashz
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Re: 86 Suburban Lift and gearing questions

I concur with the advise above. I had 35" tires on my 83 with 4.10 gears and found that to be a good set up for towing and mild off-roading. I wouldn't go higher. 4.56 would be good too, but depends on availability.

It sounds like you are going to swap 3/4 ton axles in to simplify the gear swap, which is probably a good idea. The 10 bolt rear can get a little stretched with big tires and deep gears.
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