installed gryphon

[robandkat]

I just received my gryphon, and installed it. It did not make a huge differance in the tow mode. I played with the performance 91 tune and it was better, but I thought it would make more of a differance(I was running 91 gas). I ordered an 87 custom tow tune and an 87 custom performance tune. Are these tunes going to wake the truck wake up alot more than the canned tunes? Also, should I order a custom 91 tune, would it be that much different than an 87 custom tune?

I also used 2689mm for 305/65/18 bfg at/ko tires that are 33.7 inches. This should correct the speedometer right?

After I get the custom tunes, if I change tires sizes, can I just change it in the tuner or do I have to get my tunes redone for the new tire size?

Sorry for all the questions. Any other suggestions would be greatly appreciated. I did not mess around with any other custom features because I am not sure how they would affect the truck.

Thanks for your help and suggestions!!

[robandkat]

Thanks for the info Corey. I think my tire size hurts the performance.

I also used 2689mm for 305/65/18 bfg at/ko tires that are 33.7 inches. This should correct the speedometer right?

After I get the custom tunes, if I change tires sizes, can I just change it in the tuner or do I have to get my tunes redone for the new tire size.

With my CAI and the canned tow tune it seems to drone alot (sounds like a vibration in the CAI) will the custom tunes help with that. I didn't notice it as much in the canned 91 tune. Sorry for so many questions this is all new to me.

[Caforddude]

Your custom tunes will make a world of difference.

Would be just like the difference between a track home and a custom home. The track home will be nice and probably suit your needs for a long time but a custom home will have that counter exactly where you want it or that sink at just the right height.

You really get EXACTLY what you want when you order a custom tune from PHP. More throttle, less throttle, torque etc...whatever you want.

[Jackpine]

Originally Posted by robandkat

Thanks for the info Corey. I think my tire size hurts the performance.

I also used 2689mm for 305/65/18 bfg at/ko tires that are 33.7 inches. This should correct the speedometer right?

After I get the custom tunes, if I change tires sizes, can I just change it in the tuner or do I have to get my tunes redone for the new tire size.

With my CAI and the canned tow tune it seems to drone alot (sounds like a vibration in the CAI) will the custom tunes help with that. I didn't notice it as much in the canned 91 tune. Sorry for so many questions this is all new to me.

Hey! Another guy who includes his Wife, Sweetheart, whatever in his screenname! Good on you buddy!

Bill will be able to reduce or eliminate the drone your CAI is causing. The fact that you are getting a drone with the tow tune though is evidence that the canned tune is doing "something". I could immediately tell the difference between my canned tow tune and stock when I first got the programmer. Primarily, I found downshifts were happening much more quickly and were completing quickly. There was none of that, "I wonder if this thing is ever going to speed up?" when I was trying to pass someone. I also noted an increase in gas mileage.

The custom tune seemed to refine it even more and I got a further increase in gas mileage.

But, these are heavy trucks and a tune is not going to make them into top fuel dragsters.

The Tire Size (TS) you entered does not account for "squish" - the flattening of the footprint that actually reduces the rolling radius. I've found that if you reduce the unloaded circumference by about 3%, your speedometer and odometer will be much more accurate. In your case, try subtracting 81mm from the circumference and entering 2608mm. When Bill writes your custom tunes he will use a "squished" value for the tires you say you have.

If your stock tires were 275/65R18 (like mine) and your Gear Ratio (GR) is 3.73, the effect of mounting the larger tires was like reducing your GR to 3.55. You'd need to install 3.90 gears to get your old "zip" back.

BEFORE you change the TS (and GR) in your Custom Options menu, please take the time to read the Q & A I posted on this here: http://dygytalworld.ehost-services13...ead.php?t=1101 (It's in the FAQ section of the Gryphon forum). Custom Options are an easily misunderstood process, so please make sure you know what you're doing.

Finally, welcome to the forum!

- Jack

[robandkat]

Jack, thanks for all the helpful info. I will check out your Q&A page. Do you think that I should change the gears? My wife uses the truck to commute to work and to pull a two horse trailer.

[Jackpine]

Originally Posted by robandkat

Jack, thanks for all the helpful info. I will check out your Q&A page. Do you think that I should change the gears? My wife uses the truck to commute to work and to pull a two horse trailer.

Two horses are what, about 3000#? Then the trailer is another 1000-1500 I guess. I'd rather see the original effective gearing in this setup because what you have puts a strain on your transmission. However, I think it will handle it.

The reason you like a high gear ratio for towing heavy loads is because the transmission output shaft then "sees" very little "load", and this lets the transmission operate with the Torque Converter locked most of the time and without having to downshift so much. The downside of high gear ratios though, is decreased fuel economy. Trouble is, with a 4x4, you have to replace BOTH sets of gears. Probably about $3000.00? (I'm guessing here, and it's a real "WAG").

The effective gear ratio of 3.55 you have with 3.73 gears (and I'm pretty sure that's what you have) is not bad, it's just not designed particularly for towing. However, as a daily driver, it's just fine.

One thing to do is monitor the Transmission Fluid Temperature. I pull a 3600# trailer and have seen it get up to about 214 when pulling up a steep, long grade. If you see it getting significantly above this, you need different gears.

Poke around in our new "towing" section. I'm tempted to move this there, but I'll leave it here for now. There's some really good information there about how people dealt with the need to pull really heavy loads.

- Jack