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Old 02-05-2018, 12:37 AM   #26
rideair
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Re: New to squares

mongocanfly, point well taken.

I live out in the Shenandoah Valley in Virginia (where they say, y'all) but often travel to Washington, DC for work, so I fully understand your point.

Washington, DC. To small to be a state, to large to be an insane asylum!

Enjoy,
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Old 02-05-2018, 01:08 AM   #27
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Re: New to squares

I'm kind of forced to take the interstate between home and work so going slower isn't an option. Thanks for the suggestions though.
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Old 02-07-2018, 10:09 AM   #28
Edahall
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Re: New to squares

These trucks were not really designed to drive at a sustained 80 mph cruising speed. With an anemic 350 engine in a lifted 4x4, the engine will be close to maxed out at 80 mph. I would look into installing a larger engine like a Cummins 5.9 turbo diesel or a 8.1 Chevy gas engine. The 8.1 will still get poor fuel at 80 mph but you would have some throttle to spare while the Cummins will still get around 17 mpg at 80 mph. I would also get rid of the lift and get some tires rated for high speeds. Having a blow out at 80 mph in a lifted truck is not fun and sometimes fatal. Also look into upgrading the brakes. Convert to hydroboost and rear disk brakes.

Last edited by Edahall; 02-07-2018 at 10:51 AM.
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Old 02-07-2018, 10:17 AM   #29
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Re: New to squares

Engine swap is a super expensive, time consuming option. I would drop the lift to 2.5" and then if absolutely necessary, drop the tire size to 31" or 32". Otherwise, I'd just drive it as is.

If it was me, I like the look of 33" tires with a 2.5" lift vs. a 4" lift. I personally think the 4" looks too high for me.

This does look like a 1/2 ton truck (6 lug wheels), so should have the 4 speed OD, 700R4 tranny.
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Old 02-07-2018, 11:23 AM   #30
Abomb1
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Re: New to squares

Engine swap is an expensive option I'm not ready for now. I wouldn't mind dropping it down to a 2.5" lift though if I could get by without spending a bunch of money to do it. Guessing it would require different front leaf springs and a shorter block in the back? I should still be able to use the 33's with the smaller lift?
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Old 02-07-2018, 11:46 AM   #31
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Re: New to squares

Quote:
Originally Posted by Abomb1 View Post
Engine swap is an expensive option I'm not ready for now. I wouldn't mind dropping it down to a 2.5" lift though if I could get by without spending a bunch of money to do it. Guessing it would require different front leaf springs and a shorter block in the back? I should still be able to use the 33's with the smaller lift?
Yes, usually no problem at all. I'm running 35" tires with a 2.5" lift.....slight rubbing if I hit a big bump while turning, but haven't really had it happen in several years with this setup. Rim size for me is 15x8. You may have 15x10....hard to tell.

You could get BDS front springs or Tuff Country. Then new blocks in back and new Axle Ubolts. The only question would be the shocks that are mounted. Some can handle a little bit of drop, but you'd have to check out the model numbers to see if it could handle the lower ride height.

Here is mine with a 2.5" lift and 33" tires.
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Old 02-07-2018, 11:48 AM   #32
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Re: New to squares

And just for fun when I first bought it....

37" tires on 2.5" lift. Yea, didn't last too long after I bought it!
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Old 02-07-2018, 12:31 PM   #33
Edahall
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Re: New to squares

One no added cost thing you can do to keep the transmission from hunting between overdrive and direct drive at 80 mph is to manually select 3rd gear on the column shift. This would keep the engine in the max power band, possibly increase fuel economy and prolong the life of your transmission.
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Old 02-07-2018, 03:12 PM   #34
68Timber
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Re: New to squares

Lowering the truck to a 2.5" lift "should" help, right? You're getting the truck a little bit closer to the tires and hopefully it'd help with wind drag under the truck. But I wouldn't install a 2.5" lift unless that's the lift you really want because I don't think it's going to fix the problem you asked about.

Like everyone else mentioned, the truck has the aerodynamics of a billboard and the TBI 350 wasn't a powerhouse. The truck's already been regeared properly for the tires, the only sure fix now is horsepower, or more accurately, torque.

I don't mean to be a killjoy because I love your truck and I'd DD it but if it were me I'd leave 15 minutes earlier every day, slow it down to 72 or 73, and enjoy driving a badass truck.
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Old 02-07-2018, 03:18 PM   #35
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Re: New to squares

^^ Agree 100%.
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Old 02-08-2018, 09:18 AM   #36
Edahall
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Re: New to squares

Since your transmission is hunting between 3rd and overdrive at 80 mph, just manually shift it in into 3rd. You'll at least prolong the life of the transmission. I calculated the RPMs.

2343 RPM, O/D @ 80 mph
3437 RPM, 3rd @ 80 mph

The 350 develops more power at 3437 RPM than 2343 RPM and your 350 engine should be happy running at 3500 RPM.
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Old 02-08-2018, 10:40 AM   #37
Abomb1
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Re: New to squares

Quote:
Originally Posted by Edahall View Post
Since your transmission is hunting between 3rd and overdrive at 80 mph, just manually shift it in into 3rd. You'll at least prolong the life of the transmission. I calculated the RPMs.

2343 RPM, O/D @ 80 mph
3437 RPM, 3rd @ 80 mph

The 350 develops more power at 3437 RPM than 2343 RPM and your 350 engine should be happy running at 3500 RPM.
Thanks, this is what I've been doing, but good to know it should be happy at that rpm.

I'll see what I can do with giving myself more time, but I'm usually in a rush after work to get 1 or more of the kids on to their activities.
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Old 02-10-2018, 08:45 PM   #38
427Carl
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Re: New to squares

Quote:
Originally Posted by 68Timber View Post
Lowering the truck to a 2.5" lift "should" help, right? You're getting the truck a little bit closer to the tires and hopefully it'd help with wind drag under the truck. But I wouldn't install a 2.5" lift unless that's the lift you really want because I don't think it's going to fix the problem you asked about.

Like everyone else mentioned, the truck has the aerodynamics of a billboard and the TBI 350 wasn't a powerhouse. The truck's already been regeared properly for the tires, the only sure fix now is horsepower, or more accurately, torque.

I don't mean to be a killjoy because I love your truck and I'd DD it but if it were me I'd leave 15 minutes earlier every day, slow it down to 72 or 73, and enjoy driving a badass truck.
The truck is awesome . identical interior to the 2wd 88 I just bought
try the lower height and smaller tires . Do not give up and sell it . It history and deserves to be saved . and keep out of snow ?
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