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IAS install & tire pressure question


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So we got the IAS shocks installed last night.  We started at 7pm and finished at 9pm, with minimal BSing and no beer breaks. Once we got the truck up on 4 jacks, so I could rotate the tires too, it went fairly quickly and easily.  The one snag we hit was on the rears when we had put the left rear on the right rear and had to swap when we realized the difference.  The problem was that we had already cut the restraining strap on the left one and then had to muscle that SOB closed to fit in the bottom bracket.  Other than that, piece of cake.

 The road from my bud's place is 5 miles of gravel and washboards back to the paved road. I could immediately tell a firmer difference. Still a little bouncy in the rear, but I had no weight in the bed. Once on the paved road I took it through a very narrow and winding canyon road and kept saying, "Wow!" It dramatically improved the body roll and definately had the sport car feel they advertise.  I put about 20 miles on it and came home.

This morning I had to drive 60 miles to the next town for a brake job, through the same canyon road and was still saying, "Wow!" Lost the last of the steering wheel shimmy, hit curves with no thoughts of braking and beat my fastest time by 3 minutes while passing several cars.  I was even thinking that I need more power now that it handles better.

After the pads were replaced, my mechanic told me he saw no suspension problems and that I should see how rotating the tires and new shocks affect it before getting an alignment.  Cool, saved me ?+.  Then he asked if when we rotated did we change tire pressure too. No, because I usually run 50psi all around. He said to try 40psi in front and 60psi in rear. So he added and let air out but while driving around town it seemed a little "mushy" so I stopped and aired the fronts back up to 50psi, and then headed home.

 Well the whole ride home the rear end was bouncing considerably more and riding a little rougher than it had this AM on the same road.  Now the wind was ripping across the road most of the way home, but I couldn't believe how it seemed I had my old shocks back on! It still handled great in the curves but boy it was not as smooth as earlier.  I'm letting it cool for awhile and then I'm going to change the air back the way it was, but can 10 little psi make that much difference?  Maybe combined with the wind howling, blowing me around the road? The door decal says 50psi and 80 psi, but I can't see going up to 80 if 60 felt too much.  Any thought on this long winded diatribe?

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Checked the rears with a gauge that goes over 50psi (mine doesn't), he actually had over 70psi in them.  Dropped them back to 50psi and took a little ride-all better! Think I may have found a deal on some 285's finally.  Going to Discount Tire on Thursday and see how they fit.

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Just a thought, remember when you go to a 285 tire, it most likely will not be in a "D" or "E" load range.  Most 285's I've seen are all "C" rated which will have a lower psi for inflation.  Since your truck is a 3/4 ton, I'd be careful about putting anything but "E" range tires on in my opinion.  Also, if you go with a "C" load range tire then the placard on the door jamb of the truck will be inconsistant with a most likely 50 psi on the 285's.  Not to say that you "can't" do this cause many people do, just be careful if towing up to a 3/4 ton capacity with the "C" load range.

As for the IAS, I think you'll notice even a bigger difference after about a month of driving.  Many folks at the Sub forum have them and mention the break-in period of about 3-4 weeks (also suggested by Edlebrock) gave even better ride.  Nice shocks but a bit goofy having to install them upside down compared to others.

HTH,

BIG BLUE

(Edited by BIG BLUE at 11:25 pm on May 29, 2001)

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As long as your are running empty you could easily run 45 lbs in your tires with no problems.  If you are carrying a heavy load for a distance or towing then air them up a little.  I ran them lower in my '97 F250 unless I was towing or carrying a load and didn't have any problems.  I was running 265's on the truck load range "D".

I also had the IAS shocks on that truck and loved them!!!  They were pricey but I though they were GREAT!!!  You'll really like them too...

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Big Blue-

The tires I found were on the Discount Tire web site (www.discounttire.com) and they show you load ratings. I specifically asked for the ones with D load. I am currently rolling on 245's with an E load from Wild Country, they came with the truck.  DT had 3 or 4 choices in a 265 or 285 with the D load rating.  I am going to check on the ones I am looking at, but some D loads actually have more max weight than some E loads.

 I am looking at Pathfinders which are made by BFG, but about ? less per tire, but have the same tread pattern as the BFG KO's with a 60K warranty. 285 BFG KO's x 4 =?, mount+balance+road hazard.  285 Pathfinder AT's x 4=?, m+b+r.h. I turn the white letters in, so I don't care whose name is on them as long as they perform. Plus the DT guy said since I'm driving 3 hours to them, (I live in the middle of nowhere) if they were sold, he'd put some Goodyear Wrangler AT's on at Pathfinder price. Plus they'll put a 285 on to see if they fit before selling me 4.

 The other thing is I'm thinking of keeping the 245's for next winter when I'm towing sleds or just selling them myself. (Not towing or hauling much this time of year, 'cept a few fishing rods). Lots of tread left, I'm just trying to beef up my truck and the 245's look a little small.

 Shaners you probably don't want to hear about the steal I got the IAS's for, with free shipping and a rebate.  I justified the price by doing the labor myself.  Probably about even what I would've paid for some ? gas NAPA shocks installed! Looking forward to a smoother, unloaded ride-

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