H3 Couple of questions

[snoman48]

Hey gents,

So I've had the H3 for about 6 months now, and I've got a few questions that I figured I'd bundle together in one thread to avoid clogging up multiple areas.

Basics on the truck: 2008 H3 Base, I5 3.7L with manual tranny, 66xxx miles.

First question is for those with a manual; When I'm idling, say at a stop light or whatever, if I take my hand off of the shifter and let it sit, it starts to vibrate both visibly (understandably), but more so audibly. Unless I leave my hand on it, or stay in gear, it buzzes pretty good. Is this a common thing for you guys? Or is there something underneath I should look for to tighten up?

Secondly, for those with the Schwarttzy "Simply Aux-In" mod (the adapter that makes a aux in port as a jumper through the XM channel), I get a high pitched intereference noise when I use it, that follws engine RPM. I've tried changing out my aux cable to a higher grade / better shielded one, and using other devices, but it stays, leading me to believe that it's the adapter itself. Anyone found a fix for this?***UPDATE*** It's my charger for the ipod, not the adapter at all. Problem fixed until I get a better charger!

Lastly, my tires are shot, and I'm about to buy new ones. I'm keeping the OEM rims, but I'd like to go up in size. If my searches have been accurate, I can run 315 75/R16's with no problem correct? I have no suspension modifications done, or torsion bar crank performed; just bone stock. I'm choosing between BFG T/A KO's and General Grabber AT2's, as I can get them at essentially the same price.

Any and all input is appreciated, thanks for the help!

-Snoman

 

[H3slate]

My shifter visibly vibrates when idling, but don't think it makes noise too.

On the tires, you can definitely fit 315/75/r16's on your truck. They will make a big improvement on the look of your truck. You can't go wrong with the BFG's, I have duratracs and have been pretty happy with them.

 

[snoman48]

Thanks slate!

Good to hear about the tire size being okay, I definitely don't like the look of huge wheel well gap. Your sig says you cranked your T-bars, did you do that because you put the 315's on? Or just wanted to level things out?

When I replace the shifter, I'll probably pull everything apart and look for something a bit loose. Still have that Hurst T-Handle on my to-do list. Was just wondering if anyone else had found it.

 

[SuperBuickGuy]

before you drive off from the tire shop, be sure the 315s work.... most base H3s can only go 305s because the wheel offset isn't enough to keep them from rubbing.

 

[frumaker]

You can definitely run the 315 with only minor rubbing at full lock and it may not even be enough rubbing that you will notice.


FRU

 

[H3slate]

The rubbing with oem wheels is not bad, it only occurs at full lock. I also had rubbing with my stock 33's. I had cranked my t-bars because I really liked the leveled look. I have since put in extended shackles and have a more nose down look now.

On the shifter, there is a bolt that holds the top part of the shifter in place, maybe it is loose. Another thought, I had a Styrofoam rubbing sound when I first got my truck. It was coming from the side of the shifter boot. It eventually went away.

 

[snoman48]

Thanks all, I was playing with a tape measure today to see how the rough clearances would be, full lock does seem like the only potential bit of rub. I think I'll live with that :thumbs: . The only offroading I do is Upstate NY to get to my shooting site and cabin, so otherwise it's just my commuter.

Anyone have any input on the aux-in engine noise coming in as a high frequency sound? I was thinking maybe pulling schwartzzy's adapter out, and trying to insulate it a bit heavier.

 

[snoman48]

Also, how far should I expect my speedo to be off going from the stock tires to 315's? Anyone got a good online calculator? I'm guessing the only way to correct it is a PCM flash, or something along those lines? I might try to get my wife's dealership to help me out if that's the case:huh:

 

[SuperBuickGuy]

Also, how far should I expect my speedo to be off going from the stock tires to 315's? Anyone got a good online calculator? I'm guessing the only way to correct it is a PCM flash, or something along those lines? I might try to get my wife's dealership to help me out if that's the case:huh:

it will depend on what your stock tire size was - 265 =31", 285=33", 315=35" .... going from 31 - 35 = 11.4% meaning the speedometer will read 11% slower than you're actually traveling. Of course, all tire sizes are nominal; so you do need to measure your installed height then do the calculation (ages ago, I had 35" tires that actually measure 32.9")

 

[cbetts]

1) My shifter used to do the same. The rubber bushing got soft and allowed vibrations to travel all the way up. Now it is quite noticeable since I swapped it out for a short stroke, solid shifter.

2) Don't have the Schwartzzy adapter

3) I am running 315/75s on mine. I did some damage to my front inner fenders by having the steering fully locked to one side while fully articulating. I fixed this by installing a 1" body lift.

 

[5gn-h3t]

I don't have the Scwartzzy adapter, but I did a DIY audio mod that's basically the same thing. The audio wires need to be shielded and the input and output from the AUX jack need to be separated. Check to see if the wires are close to any other power wires behind the dash.

 

[snoman48]

Thanks all!

 

[Xlr8n]

As far as your tire choice goes, both are a good AT tire and an excellent choice for a DD rig.

Having used both I'd say I like the Grabber a bit better. The voids in the Grabber AT2 are a bit more agressive for offroad while giving no ill effects on pavement. Excellent highway manners. The more elongated voids on the Grabber seem to clear mud better than the BFG's. I'd assume the same for snow, but I haven't got to run the Grabbers in snow yet.

The deciding factor for me was that in the 305 size I wanted, the BFG's were only available in an E rated while the Grabber was a D rated which meant 2.5 lbs lighter per tire and much more compliant ride.

Usually you can find the Grabbers a bit cheaper than the BFG's.

 

[snoman48]

The price difference between the 2 is usually between $10-20 as far as I've found. I'm curious as to why you wanted the 305's instead of full 315's? I'll definitely be traveling much more snow than mud, as I commute in NY winters and my job doesn't shutdown for practically anything (I even got called into work during Sandy). I do pull a trailer occasionally as well, but I think they'd be fairly equal in that aspect. How many miles do you have on your Grabbers now? They wearing well?

 

[Xlr8n]

Only have a couple months, few thousand miles on this set of Grabbers so they are still looking new, but are working very well.

After much contemplation and research, I decided on the 305's to maintain the same factory wheel circumference as the 285's while avoiding the loss of power and braking that comes with much heavier, larger diameter wheels. The 305's are obviously only 1 cm less wide than the 315's. The 305's were about 6 lbs lighter per tire than the 315s in the Grabbers.

I played around with a few different sizes of tires over the years on my TJ Rubicon and realized that there is a lot of give and take when going with bigger tires on any given vehicle. Seeing how my H3 is my DD, I wanted to preserve as much power as possible on an already underpowered rig while still having the benefit and looks of more aggresive, trail-worthy tires.

Very happy with the way the 305's help to fill the wheel wells as well as the fact that the rig has not suffered any appreciable loss of power on the road like most folks report with larger sizes.

 

[snoman48]

Update! The interference noise I was getting from my aux-in is not Schwartzzy's harness or adapter at all! I realized on my way into work that I only get the sound when the ipod is charging, so that's my problem. When just on it's own battery there's no sound what-so-ever besides music. Schwartzzy's aux-in works great, and I'd recommend it to anyone.

Xlr8n, now you've got me considering the 305's instead, I didn't realize there would be such a weight difference. I think our driving situations are fairly similar, and you make good points. Now to research the 305's availability! Could you post up a quick pic of your H3 with the grabbers if you have one? Do you get any rub at full lock?

*Edit* Now that I've started searching the 305's, it's nice to see the huge price difference between them and 315's. With a baby on the way, I'm pretty settled on that size now. My question is, 305/75R16 doesn't exist. I'm assuming you're running 305/70R16 correct? And they fit stock wheels no problem? I'm a bit shaky with reading tire sizes, but I'm pretty sure stock is 265/75R16. So with the 70 I just lose 5% of the sidewall height right? Any tire techs feel free to chime in and educate me :thumbs:

 

[Steve #1]

I had the same problem with the shiftier but I cant recall what the issue was. I think the fix included a bit of silicone spray. I also painted the chrome cap on the snifter as I found it rather annoying when it was vibrating and caught the sun.

 

[evldave]

Update! The interference noise I was getting from my aux-in is not Schwartzzy's harness or adapter at all! I realized on my way into work that I only get the sound when the ipod is charging, so that's my problem. When just on it's own battery there's no sound what-so-ever besides music. Schwartzzy's aux-in works great, and I'd recommend it to anyone.

The feedback from cig chargers is common with this mod - I have a similar one (did it myself) and get feedback from mostly cheap power adapters. I think the wiring for the cig lighter runs near the wiring for the radio and XM (except it's not shielded). When you use a cheapo adapter, it backfeeds. When I use a different power circuit it doesn't do it, and if I use a nice (OEM) 12v adapter, it rarely does it. If you find other power adapters that feed back through the radio, try running a separate power wire and see what happens (if you aren't comfortable with that, just try powering your phone from the rear power socket while the car is running and see if you have the whine sound).

 

[Xlr8n]

Update! The interference noise I was getting from my aux-in is not Schwartzzy's harness or adapter at all! I realized on my way into work that I only get the sound when the ipod is charging, so that's my problem. When just on it's own battery there's no sound what-so-ever besides music. Schwartzzy's aux-in works great, and I'd recommend it to anyone.

Xlr8n, now you've got me considering the 305's instead, I didn't realize there would be such a weight difference. I think our driving situations are fairly similar, and you make good points. Now to research the 305's availability! Could you post up a quick pic of your H3 with the grabbers if you have one? Do you get any rub at full lock?

*Edit* Now that I've started searching the 305's, it's nice to see the huge price difference between them and 315's. With a baby on the way, I'm pretty settled on that size now. My question is, 305/75R16 doesn't exist. I'm assuming you're running 305/70R16 correct? And they fit stock wheels no problem? I'm a bit shaky with reading tire sizes, but I'm pretty sure stock is 265/75R16. So with the 70 I just lose 5% of the sidewall height right? Any tire techs feel free to chime in and educate me :thumbs:

The 305's are indeed 70 series, which will be nearly identical in tire height to the 285/75 16's that came stock on the adventure pkg H3's. They do rub a tiny bit at full lock, but only at complete full lock and even then it's only marginal and it doesn't hurt the tire at all. With the extreme turining radius of the H3 you won't need to be at full lock in many situations.

The 305's are listed to fit a bit wider wheel than the stock H3's, but they fit fine and if you run them at around 32-34lbs you'll get nearly a full contact patch and a very compliant ride. You don't need a D rated tire aired up to the sidewall recommendation for a vehicle weight like the H3 with no real payload to speak of.

I ran 285 Nitto AT's on my Jeep at 28-30lbs to get a proper contact patch and got over 60k miles out of them and they still had good tread when I sold it.

Here's mine on 305 Grabbers. Just got the matching spare mounted up yesterday.

 

[Gunick]

just my .02 but for the l5 motor owners who are the weekend warriors, 285/305's seem to be the better size to go with. easier on rig, no altering to stop rubbing, power stays fine and doesn't absolutely murder your mpg's. the 315 look is obviously better but if you commute more, sometimes the 305's make up for the difference in look haha

 

[snoman48]

Steve: That glare from the chrome cap is murderous on my ride to and from work! That's half my reason for going to a T-Handle!

Dave: Good ideas, I'll give the rear socket a try later on and see how it does. Actually never realized I had a rear socket The power adapter in my cig lighter is just a cheap duracell twin USB charger, so I'm not surprised it's the problem.

XLr8n: The grabbers look great on your truck! I'm pretty settled on those now, just waitin on my paycheck to hit to order them! Mavis has them for $189 each, so that's a nice price relief from the 315's I was originally looking at. Do you run your 32-34 psi for highway travel? I was thinking of running 'em a little harder for commuting, then airing down to about there for my small offroading.

Gunick: I completely agree now. I'm pretty settled on the 305's, just better for my situation all around.

I'm thinking of plasti-dipping the wheels black after the new tires are mounted, the salt from my wonderful NY roads has done some wear to the finish of my rims, so I think dipping them will clean up the 10-foot-look test nice enough. Plus black on black looks pretty nice on these trucks IMO. Anyone plasti-dipped their stock wheels through a NorthEast winter/anywhere else they use salt more than snow? How'd it hold up?

 

[H3slate]

I hated the glare from the shifter too. Painted it to match my wheels. Now there is slightly less glare.

Sent from my mobile bat cave using Tapatalk 2

 

[Bigunit]

I plasti-dipped my entire front windshield and chrome HUMMER letters on the tailgate of the T as I could no longer deal with the glare. Problem solved. Just can't' see **** out of the front windshield. Have to now drive everywhere in reverse.

Sent from my DROID RAZR using Tapataint

 

[PreferredChassisFab]

I plasti-dipped my entire front windshield and chrome HUMMER letters on the tailgate of the T as I could no longer deal with the glare. Problem solved. Just can't' see **** out of the front windshield. Have to now drive everywhere in reverse.

Sent from my DROID RAZR using Tapataint

It never stops......

Sent from my C771 using Tapatalk 2

 

[Xlr8n]

Steve: That glare from the chrome cap is murderous on my ride to and from work! That's half my reason for going to a T-Handle!

Dave: Good ideas, I'll give the rear socket a try later on and see how it does. Actually never realized I had a rear socket The power adapter in my cig lighter is just a cheap duracell twin USB charger, so I'm not surprised it's the problem.

XLr8n: The grabbers look great on your truck! I'm pretty settled on those now, just waitin on my paycheck to hit to order them! Mavis has them for $189 each, so that's a nice price relief from the 315's I was originally looking at. Do you run your 32-34 psi for highway travel? I was thinking of running 'em a little harder for commuting, then airing down to about there for my small offroading.

Gunick: I completely agree now. I'm pretty settled on the 305's, just better for my situation all around.

I'm thinking of plasti-dipping the wheels black after the new tires are mounted, the salt from my wonderful NY roads has done some wear to the finish of my rims, so I think dipping them will clean up the 10-foot-look test nice enough. Plus black on black looks pretty nice on these trucks IMO. Anyone plasti-dipped their stock wheels through a NorthEast winter/anywhere else they use salt more than snow? How'd it hold up?

yeah running them at 33 psi for DD. Full contact patch and compliant ride. You might save a mpg or two by airing them up higher and only running on the center of the tread, but they'll ride rougher and you'll wear the centers down twice as fast.

Plastidipped my emblems last year and ran them thru a salty midwest winter with no issues. Stuff holds up great, even through carwashes and such.