Does a axle re-gear require a ECU tune?

[stutaeng]

I had never wondered this until today. Will go from 3.42 to 4.10s, after swapping 4.3 to 5.3/4L80e. The 5.3 came with it's own ECU and need to get VATS deleted, and reflashed for the 80e. Would like to do the reflash/reprogram all at once if rear ratio needs to go into the ECU.

I don't know anything about ECU tuning.

 

[PlayingWithTBI]

Yes the newer PCMs feed the speedometer plus it kinda needs to know how fast you're going for trans shifts and TCC lockup.

 

[stutaeng]

Ok, thanks! I guess I'm trying to decide everything so I just have to pay for re-tune once. I never realized it, but the 80e 1st and 2nd gear ratios are different than the 60e. I think that's why a lot of guys doing the swap notice that the 80e "robs" more power.

Regear was on my plan anyway. I'm happy with my other trucks that have the 4L80 with 4.10s, even though they are 14 bolts. I would imagine it will work well on the 10 bolt 1500 2wd too. Will be occasionally towing a trailer for work. Those 6x12 enclosed trailers from Uhaul is what we've used before. They have a GVWR of 4,400 lbs.

gear 80 vs 60
1. 2.48 vs 3.059
2. 1.48 vs 1.625
3. 1.0 vs 1.0
4. 0.75 vs 0.696

Lastly, my truck has the G80, which I would like to keep. Should just swap ring gear and pinion gears, right? My nephew knows a guy that does these for like $200 labor only. I don't think I can beat that!

 

[PlayingWithTBI]

My nephew knows a guy that does these for like $200 labor only. I don't think I can beat that!

Yeah, around here it's about $300. My son and I did mine ourselves, saved some $$$.

 

[df2x4]

I guess I'm trying to decide everything so I just have to pay for re-tune once.

Depending on who does your tuning this may not be a huge issue. I know Black Bear Performance offers free re-tunes for life as long as you pay shipping on the PCM, which is around $14 for USPS Priority flat rate.

 

[Nickpisp]

Ok, thanks! I guess I'm trying to decide everything so I just have to pay for re-tune once. I never realized it, but the 80e 1st and 2nd gear ratios are different than the 60e. I think that's why a lot of guys doing the swap notice that the 80e "robs" more power.

Regear was on my plan anyway. I'm happy with my other trucks that have the 4L80 with 4.10s, even though they are 14 bolts. I would imagine it will work well on the 10 bolt 1500 2wd too. Will be occasionally towing a trailer for work. Those 6x12 enclosed trailers from Uhaul is what we've used before. They have a GVWR of 4,400 lbs.

gear 80 vs 60
1. 2.48 vs 3.059
2. 1.48 vs 1.625
3. 1.0 vs 1.0
4. 0.75 vs 0.696

Lastly, my truck has the G80, which I would like to keep. Should just swap ring gear and pinion gears, right? My nephew knows a guy that does these for like $200 labor only. I don't think I can beat that!

No decent tuner will charge you to change little things like that.

The 4L80E “robs” more power because everything in it is heavier, more mass to turn.

 

[Supercharged111]

No decent tuner will charge you to change little things like that.

The 4L80E “robs” more power because everything in it is heavier, more mass to turn.

Yeah, like the giant assed 80# torque converter to start with. If you could get one 30# lighter or so with the same stall you'd see a huge difference in acceleration.

 

[stutaeng]

Yeah, like the giant assed 80# torque converter to start with. If you could get one 30# lighter or so with the same stall you'd see a huge difference in acceleration.

Yeah, that thing is beefy! When I went to pick mine up, 2 guys could not pick it up because the bell housing end was insanely heavy. Didn't help that it was still full of fluid either.
We had to take off the torque converter! LOL.


Lawrence Tolman "LT" has a series on YT on a '00 ECSB that's really cool. He did a 8.1/4L80e/4.30 swap!

I'm just doing a reliable setup. Nothing crazy.

 

[PlayingWithTBI]

Yeah I like all their series on Motor Trend TV - Truck Tech, Engine Power, Detroit Muscle, XOR, among others.

 

[stutaeng]

Here's the series:

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