Wheels and tires causing a few problems

[MarcuM]

Hey all 

I recently went to some 18x12  -24 moto metals with mt Baja Mtz tires and they are measuring out at around 32” from my stock wheels with 265s on my 2016 5.3 6sp cc 3.42gear

 

Mpg went from 21 to 13 avg 

trans temp up from 188 to 194 constant on highway

power feels like my old 4.8 now 

 

I got a hypertech 2.0 tuner but no help really 

I expected possibly a loss of 2-3mpg but this is a little much 

I had planned to go 6” with 35s but there’s no way now unless these Mickey Thompson’s are causing way to much rolling resistance has anyone else had this big of a lose with mud tires or offset rims ?

[DominatorZ71]

Your gears are too small. You need bare minimum 3.73 for some 35s and even then 4.10 is recommended. 3.42s are what's killing you.

[1SLOW1500]

Gearing will help. But it can all. Be fixed in tunning. The torque management only gives you 30% of the line so think what would happen if you had 70% more more. Also tighten up the shifts and remove dod. I would update tire size but also the traction value. The 6speed is good with inproved shifts and dod removed slip values changed based on truck use. I personally believe for the money intake and exhaust and full tune are a stage 1 setup. Great base for anything else. 

Or if it's in you budget the are supercharger kits with gm warranty 560rwhp. But again exhaust would help. And tune always. 

[FlipZ71]

7 hours ago, MarcuM said:

Hey all 

I recently went to some 18x12  -24 moto metals with mt Baja Mtz tires and they are measuring out at around 32” from my stock wheels with 265s on my 2016 5.3 6sp cc 3.42gear

 

Mpg went from 21 to 13 avg 

trans temp up from 188 to 194 constant on highway

power feels like my old 4.8 now 

 

Significant weight change..  

1slow1500 post above is spot on .. 

I'm  lifted almost 5 inch , 34inch nitro trail , BBP tuned , 2.5 inch duel , intake , 3.42 ,

Not heavy on foot I can achieve an average of 21,  my normal style average is 15...

 The tune has been my favorite mod , 

Completely changed the truck...

[swathdiver]

8 hours ago, MarcuM said:

Hey all 

I recently went to some 18x12  -24 moto metals with mt Baja Mtz tires...

No Baja MTZ tire is approved for a 12" width on an 18 inch wheel.  I was looking up the cause as folks here have posted the solution and came across that tidbit of information.  Your new tires and wheels appear to be about double in weight to the originals.

[Darksky]

Slow 1500 is spot on (again). Follow the tuning outline he provided.

 

[flyingfool]

you just added a bunch of excess weight thats probably sucking 20hp off the motor.

 

watch this video, fast forward to 5 minute mark to see the weight comparision of after market vs oem on a scale 

 

 

Edited February 10, 2019 by flyingfool

[MarcuM]

I have a hypertech tuner (not the greatest) 

but with there 93tune and shift points bumped up and shift speed turned up I think it’s worse 

I eventually took it all back to stock but the firmness and dod off and I get better mpg  

 

I have a 14mile mountain I cross before o get to my house I used to be able to cost home from now I only go about 4 miles and the truck is stopped lol

 

They are quite near double the weight of stock wheel combo but nearly identical height now that they are worn same as a new 265 tire

I recently  had some Tc lock up problems and I did a fluid change and it seemed ok but could the Tc be causing some of the poor temps and mpg as well 

I can’t imagine people pay $60k for rocky ridge trucks that get 16city 13hw and that’s with 35s on heavier rims

if I go up 3” on tire size and lift the truck I’ll be close to 11 city 9 hw I would think 

 

 

[flyingfool]

you guys with the big tires need to delete the trans thermostat or else your really gonna have serious issues down the road!

[Snowcamo]

you guys with the big tires need to delete the trans thermostat or else your really gonna have serious issues down the road!

Can you elaborate on this? Thanks.

Sent from my LG-G710 using Tapatalk

[flyingfool]

your better off using the Tahoe PPV steel rims in 17" x 9, and using a 33" tire.  you'd be amaized the steel rims weight less than the factory alloy rims. if you dont like the steel Police rims get a set of Z71 18" alloys , those will weight less than your aftermarket set up and look cool.

Edited February 10, 2019 by flyingfool

[flyingfool]

9 minutes ago, Snowcamo said:

Can you elaborate on this? Thanks.

Sent from my LG-G710 using Tapatalk
 

yes, search trans thermostat removal, on youtube. its very easy to do!!!!

OEM temps on tranny is like 185-210 degrees on the highway..after deleting you with see it drop to 120-140 degrees, less heat improves the life of the clutch packs and the TCC lock up will last longer.

Edited February 10, 2019 by flyingfool

[MarcuM]

I have looked into this because the 190 threshold is hardly ever 190 for me 

like I said above mine was a constant 188 and now it runs at 194 and never hardly goes down to 190 while I’m rolling just sets st 194 and if I get on it a little it will climb even higher on highways 

the 2 hard lines under the truck 1 is always cold and the other hot so idk if it’s working or not 

 back to mileage though I’m super good with mpg management with a 50mile best at 35mpg in my truck and right now the way it looks I will never see 20s ever agin with a 32” tire just seems odd when all these other 35” trucks riding around getting 4-5mpg better then me heavy rims or not 

[Booger T]

26 minutes ago, MarcuM said:

35” trucks riding around getting 4-5mpg better then me heavy rims or not 

Are they

[MarcuM]

I meant 33s getting 4-5mpg better 

if I’m getting what I’m getting with a 32” tire what will be the end result with 35s then?

if it stays the same I’ll be perfectly content but I can’t see that happening and there’s a ton of 35s on this site with the same or a touch better then my mpg 

Edited February 10, 2019 by MarcuM