Should I Give 3.42 A Second Chance?

[Big Whiskey]

Hey everybody, I need some advice. My current truck is a '07 VMax ECSB Z71 with 3:73 gears (leveling kit & stock tires). I'm very happy with it...good power and mpg...and stays in OD while crusing or passing. But, I've been getting the itch for a new one. I see that 3:42 gears are the lowest available (without getting the max towing pkg). I had 3:42's in my '06 5.3 ECSB (cranked t-bars & 285's), and it drove me crazy. If I sneezed too hard, or hit a head wind, it would unlock the TC or shift to 3rd gear...and it got ~13 mpg.

 

I've read countless posts about how the new 6-speed is much better than the old 4-speed...and how it's like having 4:56's with the 4-speed (in the lower gears) and like having 4:10's in the middle gears...etc......but, I'm concerned about the final drive ratio. With a leveling kit and 33's, is the 5.3 with 3:42's going to be hunting for gears every time I try to pass someone, come to a slight hill, hit a strong wind, etc? After I had that '06, I told myself I would never go back to 3:42's. Man this stresses me out!!

 

Please help!

[Z'06]

Hey everybody, I need some advice. My current truck is a '07 VMax ECSB Z71 with 3:73 gears (leveling kit & stock tires). I'm very happy with it...good power and mpg...and stays in OD while crusing or passing. But, I've been getting the itch for a new one. I see that 3:42 gears are the lowest available (without getting the max towing pkg). I had 3:42's in my '06 5.3 ECSB (cranked t-bars & 285's), and it drove me crazy. If I sneezed too hard, or hit a head wind, it would unlock the TC or shift to 3rd gear...and it got ~13 mpg.

 

I've read countless posts about how the new 6-speed is much better than the old 4-speed...and how it's like having 4:56's with the 4-speed (in the lower gears) and like having 4:10's in the middle gears...etc......but, I'm concerned about the final drive ratio. With a leveling kit and 33's, is the 5.3 with 3:42's going to be hunting for gears every time I try to pass someone, come to a slight hill, hit a strong wind, etc? After I had that '06, I told myself I would never go back to 3:42's. Man this stresses me out!!

 

Please help!

 

With the 4-spd., 3.42 with 33" tires will be a turd for off-the-line performance, not to mention adding stress to your transmission and engine and reducing your city mileage compared to 3.73 or even 4.10 (on the flip side, your freeway RPMs will be a hair lower, resulting in better highway mileage than 3.73).

 

IMO, you are going in the wrong direction and should be considering 4.10 (for primarily highway) or 4.30-4.56 (for primarily city).

[rodram]

.... on the other hand... it seems that you have found a truck that you really like (your '07)

 

.... so consider keeping it

[Matt_]

Hey everybody, I need some advice. My current truck is a '07 VMax ECSB Z71 with 3:73 gears (leveling kit & stock tires). I'm very happy with it...good power and mpg...and stays in OD while crusing or passing. But, I've been getting the itch for a new one. I see that 3:42 gears are the lowest available (without getting the max towing pkg). I had 3:42's in my '06 5.3 ECSB (cranked t-bars & 285's), and it drove me crazy. If I sneezed too hard, or hit a head wind, it would unlock the TC or shift to 3rd gear...and it got ~13 mpg.

 

I've read countless posts about how the new 6-speed is much better than the old 4-speed...and how it's like having 4:56's with the 4-speed (in the lower gears) and like having 4:10's in the middle gears...etc......but, I'm concerned about the final drive ratio. With a leveling kit and 33's, is the 5.3 with 3:42's going to be hunting for gears every time I try to pass someone, come to a slight hill, hit a strong wind, etc? After I had that '06, I told myself I would never go back to 3:42's. Man this stresses me out!!

 

Please help!

 

With the 4-spd., 3.42 with 33" tires will be a turd for off-the-line performance, not to mention adding stress to your transmission and engine and reducing your city mileage compared to 3.73 or even 4.10 (on the flip side, your freeway RPMs will be a hair lower, resulting in better highway mileage than 3.73).

 

IMO, you are going in the wrong direction and should be considering 4.10 (for primarily highway) or 4.30-4.56 (for primarily city).

 

 

He's talking about going up to a 6spd with the 3.42s... not the 4spd. Just referencing that 3.42s sucked in his old truck with the 4spd.

 

To the OP:

You'll be fine. GM meant for both 5th and 6th in the 6spd to be considered as OD gears. The main difference between the 4spd and 6spd "downshifting" at highway speeds is that the downshift in the 4spd often left the engine revving like crazy on every incline or headwind that you approached. The 6spd will downshift to 5th damn near seamlessly and maintain its speed without "over revving" the engine.

 

And on that note... 3.42s in 5th gear of the 6spd has a final drive ratio of 2.9. Compared with the 4spd in 4th gear with 3.73s which has a final drive ratio of 2.6. In conclusion.. you'll be good. If you're in mountainous terrain, throw the shifter in M5 and you're set

 

For reference:

4L60E

1st 3.06

2nd 1.75

3rd 1.00

4th 0.70

 

6L80E

First:4.02

Second:2.36

Third:1.53

Fourth:1.15

Fifth:0.85

Sixth:0.67

[RyanbabZ71]

people get to hung up on the 3.42's witht he 6 speed. There is absolutely nothing wrong with it

[caddycruiser]

people get to hung up on the 3.42's witht he 6 speed. There is absolutely nothing wrong with it

 

Yes. Discussion after discussion after discussion of "...but...before the 3:42 was the slug axle..." and little understanding in how the completely different 6-spd gearing works differently with it.

 

Give the 3.42 a chance. Yes. The 6.2L with it makes another huge difference, but 5.3L or 6.2L regardless, 3.42 and 6-spd = you're fine. Try it, as always. A test drive, even in bone stock brand new form, will let you know.

[jblakeney]

My 99 has 3.42 gears and a 4L60E......... I have never complained about it......... It will bark the tires 1-2 2-3............. If you do it just right you can chirp 3-4...... Just me..... But mine seems quite powerful with 3.42s..... But I have a 2wd...... 4wd might be another story.......

 

I am ready for a 6spd...... It will have the lowest numerical ratio possible with the 6.2l (that would be a 3.08 or 3.42 which ever I can get.... hopefully not a 3.73)............

 

Jbo

[Big Whiskey]

Thanks for the input guys!

 

So how often does it shift from 6th to 5th on slight inclines or headwinds?

 

And, when it does shift...how much smoother is it compared to the old 4th to 3rd shift? I used to hate going from 1500 rpm to nearly 3000 rpm on every little hill...especially with my aftermarket exhaust.

[WilliamBos]

My 99 has 3.42 gears and a 4L60E......... I have never complained about it......... It will bark the tires 1-2 2-3............. If you do it just right you can chirp 3-4...... Just me..... But mine seems quite powerful with 3.42s..... But I have a 2wd...... 4wd might be another story.......

 

I am ready for a 6spd...... It will have the lowest numerical ratio possible with the 6.2l (that would be a 3.08 or 3.42 which ever I can get.... hopefully not a 3.73)............

 

Jbo

Why not the 3:73? I will not own a truck, that has anything higher than that, epsecially when towing heavy loads, just doing the trans a favour.

 

JMHO.

[Baja 252]

Thanks for the input guys!

 

So how often does it shift from 6th to 5th on slight inclines or headwinds?

 

And, when it does shift...how much smoother is it compared to the old 4th to 3rd shift? I used to hate going from 1500 rpm to nearly 3000 rpm on every little hill...especially with my aftermarket exhaust.

 

I was surprised on how much mine does downshift on medium size hills, I was hoping the 6.2 would have enough power to avoid downshifting on hills all the time like my 3.73/5.3 did. But when I thought about it I realized that in 6th gear the engine is really loafing along at 70mph. It's not exactly in the peak power band, so on a hill it needs a little help. The good news is when it downshifts to 5th it's pretty smooth and quiet. The RPM's only jump up a few hundred on the downshift from 6th to 5th cause your still in an overdrive gear. When it downshifts you have tons of power.

 

Not what I expected, but I'm getting used to it and I like it. If it's real hilly, I just leave it in 5th.

[BlackSilver]

I had an 01 2WD 5.3 with 3.42 gears. It was a slug in headwinds, and on grades with any load it'd drop down two gears and rev like a rice burner, just to hold the speed limit.

[Matt_]

Thanks for the input guys!

 

So how often does it shift from 6th to 5th on slight inclines or headwinds?

 

And, when it does shift...how much smoother is it compared to the old 4th to 3rd shift? I used to hate going from 1500 rpm to nearly 3000 rpm on every little hill...especially with my aftermarket exhaust.

 

I was surprised on how much mine does downshift on medium size hills, I was hoping the 6.2 would have enough power to avoid downshifting on hills all the time like my 3.73/5.3 did. But when I thought about it I realized that in 6th gear the engine is really loafing along at 70mph. It's not exactly in the peak power band, so on a hill it needs a little help. The good news is when it downshifts to 5th it's pretty smooth and quiet. The RPM's only jump up a few hundred on the downshift from 6th to 5th cause your still in an overdrive gear. When it downshifts you have tons of power.

 

Not what I expected, but I'm getting used to it and I like it. If it's real hilly, I just leave it in 5th.

 

 

Pretty much how mine is... its so smooth/quiet that i dont even notice the downshift to 5th anymore. It's almost like it shifts before you know that the truck needs to shift, so it doesnt struggle and drop speed too much and then throw it in a low gear with high RPMs like my 4spd did.

[Big Whiskey]

Thanks for the input guys!

 

So how often does it shift from 6th to 5th on slight inclines or headwinds?

 

And, when it does shift...how much smoother is it compared to the old 4th to 3rd shift? I used to hate going from 1500 rpm to nearly 3000 rpm on every little hill...especially with my aftermarket exhaust.

 

I was surprised on how much mine does downshift on medium size hills, I was hoping the 6.2 would have enough power to avoid downshifting on hills all the time like my 3.73/5.3 did. But when I thought about it I realized that in 6th gear the engine is really loafing along at 70mph. It's not exactly in the peak power band, so on a hill it needs a little help. The good news is when it downshifts to 5th it's pretty smooth and quiet. The RPM's only jump up a few hundred on the downshift from 6th to 5th cause your still in an overdrive gear. When it downshifts you have tons of power.

 

Not what I expected, but I'm getting used to it and I like it. If it's real hilly, I just leave it in 5th.

 

 

So, even with the 6.2, it shifts a lot? Hmmm. I wonder how bad a 5.3 with 33's will be??

 

 

I had an 01 2WD 5.3 with 3.42 gears. It was a slug in headwinds, and on grades with any load it'd drop down two gears and rev like a rice burner, just to hold the speed limit.

 

That's excatly what I didn't like about my '06...and exactly what I don't want with a new one!

[welscher08]

One of the guys here at work always complains how doggy his truck is. I have the 6.0 in my truck, so i don't complain. So one day I checked the oil in my truck, and checked them in the rest (as i doubt they ever do, so i do for them) and here I pop the hood and see he has the 4.8 in his work truck! I had thought it was the 5.3 the whole time. So then i wrote down the VIN and checked his rear end gear and sure enough he has the 3.34's. He always complained going up a hill he would really have to step it down to get it to shift and take off. And with my truck with the 6.0 and 4.10's i just ride the hill out. I know this isn't really relevant to your post but yes i do understand how you can get throw off now wanting 3.42's. But we also have a 2009 with the 6 speed, I would not be afraid to get the 3.42's with that tranny. So i say go for it, just test drive first.

[Willshire]

I dont know anything about the new six speeds but my 2000 sierra is getting an upgrade to 3.73. Made the decision after the eaton posi went. At 65mph on a medium incline it shifts into 3rd but i don,t consider that to be tough on the tranny. I probably won't own six speed until 2015 because truck prices are high here in ontario. i know engineers have designed the six speed to operate seemlessly there's just something about shifting from 6-5-6-5-6 on the slightest inclines that wierds me out. Put my new rear end in on monday so i guess we'll see if it makes a difference. On that note my truck gets 18-20 mpg highway with 3.42s. Might lose 1mpg with 3.73s. Blackbear tune is in my future!