4" lift, 35's, gears and egts?

strokin6L · Apr 5, 2016

I got a buddy who has an 05 6L which has a 4" lift, 35's and 3:73's. He's running 205/100's and a RCD 68mm vgt powermax. His egts get pretty hot and is concerned. He can hit nearly 1700* in less than an 1/8th mile..cruising at highway speed in 900-1000* depending on outside temp. He wants to know if changing gears will help with egts. I think that going to a 66mm sxe non vgt will help alot. I don't know much about gearing....so just wondering if changing the gearing will help with anything. Looking for any feedback from someone with a 4" lift and 35's. Thanks!

Profuzz · Apr 5, 2016

4:30 was the best upgrade dollar 4 dollar I had done on my 06 6.0

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Profuzz · Apr 5, 2016

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strokin6L · Apr 5, 2016

Did you notice a big difference? Egts? Turbo lag?

Koda22 · Apr 5, 2016

Yea I'd like to hear a little more on this topic....

Profuzz · Apr 5, 2016

Towing he

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Profuzz · Apr 5, 2016

Profuzz said:
Towing he

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Towing heavy was the biggest difference, 65mph 2200 rpm egt 1000-1100 . DD on a race tune truck felt like it loss couple thousand # 's .Red light to red-light racing huge difference

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Profuzz · Apr 5, 2016

The change in gear ratio will aid in getting the truck moving faster ,in turn should help w / spool up ? High egts air leak ?

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scparrish · Apr 6, 2016

I am going to swap gears with the same hope that I can lower egts. I would seriously doubt he will see improvement in egts going non vgt, ask me how I know.

strokin6L · Apr 6, 2016

scparrish said:
I am going to swap gears with the same hope that I can lower egts. I would seriously doubt he will see improvement in egts going non vgt, ask me how I know.

Actually everyone I've talked to said egts would go down with a non vgt. Gotta remember...the exhaust side of the RCD 68 isn't modified like a KC or Barder!

strokin6L · Apr 6, 2016

Buddy text me and said he was thinking about 4:56 gears...I'm not a gear guy, but that seems a bit much for a 4" lift and 35's...you think?

scparrish · Apr 6, 2016

Way too much. 4.30s and 35s are already lower than factory ratios. 4.56 and 37s are lower than factory.

strokin6L · Apr 6, 2016

So...4:30's would be the ticket then with the 4" and 35's?

strokin6L · Apr 6, 2016

Also, I'm assuming the pinion gears need to get changed also along with the ring gears? Or are just the 4:30 ring gears needed?

Profuzz · Apr 6, 2016

All gears ,locker , rebuild kits & synthetic gear oil ! And mag tech covers

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scparrish · Apr 6, 2016

Ring and pinion. 4.30s are ideal for 35s and even smaller running 37s.

http://www.grimmjeeper.com/gears.html

Use that calculator to see exact numbers.

Downey · Apr 6, 2016

i would say get rid of the 100% nozzles would make a huge difference in egts.

What is he using his truck for? DD? street/track? towing? towing heavy?

cRaZy8 · Apr 10, 2016

I am on 35's, with 430's, Yukon rear locker, Yukon gears, Yukon master rebuild kits, Red Line fluids.
175/30's and an S362.
2.5" Bilstein lift coils, F350 rear blocks.

My EGT went way down with this setup, from the previous (MTW St2 VGT, stock sticks, IDP Y pipe).
I used to cruise around 900-950* on the highway.
I am now around 800-850*.
Idle EGT went from about 375-400* to around 325*.

My cruise RPM at 65-70 jumped about 250-300RPM.

Like Profuzz said, the truck feels so much lighter around town. Much snappier.
Spools the non VGT faster with these gears and sticks better than the stock sticks and VGT St2.

strokin6L · Apr 11, 2016

cRaZy8 said:
I am on 35's, with 430's, Yukon rear locker, Yukon gears, Yukon master rebuild kits, Red Line fluids.
175/30's and an S362.
2.5" Bilstein lift coils, F350 rear blocks.

My EGT went way down with this setup, from the previous (MTW St2 VGT, stock sticks, IDP Y pipe).
I used to cruise around 900-950* on the highway.
I am now around 800-850*.
Idle EGT went from about 375-400* to around 325*.

My cruise RPM at 65-70 jumped about 250-300RPM.

Like Profuzz said, the truck feels so much lighter around town. Much snappier.
Spools the non VGT faster with these gears and sticks better than the stock sticks and VGT St2.

Thanks for the feedback. He decided to go with 4.30's