Where Does Your Truck Shift Out Of First?

[Zembonez]

If I really lean on my truck in first, it doesn't shift until the damn thing sounds like it is about to float the valves. It is wound tight! Once it does shift, the drop in RPMs is pretty severe. 2-3 and 3-4 shifts seem spaced just fine. Other than WOT, the shift points seem fine.

 

4L60E Gear ratios (from GM) are as follows:

 

 

• 1st 3.059
  
• 2nd 1.625
  
• 3rd 1.000
  
• 4th .0696
  
• Reverse 2.294
  

 

 

As some of you know, I am losing the crappy 3.23 gears next week and going to 3.73 Richmonds.

 

Question is... You guys think this will alter the 1-2 gear shift RPMs at WOT or will I need to do a tune to change it? I don't know what kind of input the system is using to make the 1-2 shift. Surely it isn't solely based on TPS.

 

Any theories?

[VMax2007]

I am assuming it shifts at about 5400 RPM at WOT, right? That is actually pretty conservative (low) for these engines. I had mine bumped to 6000 RPMs in my tune. These engines love to rev.

[Zembonez]

I am assuming it shifts at about 5400 RPM at WOT, right? That is actually pretty conservative (low) for these engines. I had mine bumped to 6000 RPMs in my tune. These engines love to rev.

Yeah... somewhere just north of 5500 on the tach. It sure seems wound tight. Hopefully the regear will make it a little more livable under WOT.

[Darkanion]

I am assuming it shifts at about 5400 RPM at WOT, right? That is actually pretty conservative (low) for these engines. I had mine bumped to 6000 RPMs in my tune. These engines love to rev.

Yeah... somewhere just north of 5500 on the tach. It sure seems wound tight. Hopefully the regear will make it a little more livable under WOT.

 

AGAIN with the re-gearing...! We know you don't have any gears, Rich...!

[svensk]

Yes, get it tuned. With my 3.73 gears, and tune it holds 1st gear to 50-55mph? 2nd gear which is my favorite for highway passing will hang on until 88mph. I have a little taller than stock tire of 31.6".

[Zembonez]

Yes, get it tuned. With my 3.73 gears, and tune it holds 1st gear to 50-55mph? 2nd gear which is my favorite for highway passing will hang on until 88mph. I have a little taller than stock tire of 31.6".

Can I change WOT RPM shift points? I'd like to see the shift happen at 5100 before the torque curve falls off.

[VMax2007]

Yes, get it tuned. With my 3.73 gears, and tune it holds 1st gear to 50-55mph? 2nd gear which is my favorite for highway passing will hang on until 88mph. I have a little taller than stock tire of 31.6".

Can I change WOT RPM shift points? I'd like to see the shift happen at 5100 before the torque curve falls off.

 

 

You have the 5.3 right Jim? The Tq curve should not be falling off until nearly 6K RPM. My 6.0 is still pulling hard at 6K RPM.

 

Justin actually told me my 6.0 pulls harder longer than a 6.2 does.

[Darkanion]

Yes, get it tuned. With my 3.73 gears, and tune it holds 1st gear to 50-55mph? 2nd gear which is my favorite for highway passing will hang on until 88mph. I have a little taller than stock tire of 31.6".

Can I change WOT RPM shift points? I'd like to see the shift happen at 5100 before the torque curve falls off.

 

 

You have the 5.3 right Jim? The Tq curve should not be falling off until nearly 6K RPM. My 6.0 is still pulling hard at 6K RPM.

 

Justin actually told me my 6.0 pulls harder longer than a 6.2 does.

 

I thought he had the V6..?

[VMax2007]

Yes, get it tuned. With my 3.73 gears, and tune it holds 1st gear to 50-55mph? 2nd gear which is my favorite for highway passing will hang on until 88mph. I have a little taller than stock tire of 31.6".

Can I change WOT RPM shift points? I'd like to see the shift happen at 5100 before the torque curve falls off.

 

 

You have the 5.3 right Jim? The Tq curve should not be falling off until nearly 6K RPM. My 6.0 is still pulling hard at 6K RPM.

 

Justin actually told me my 6.0 pulls harder longer than a 6.2 does.

 

I thought he had the V6..?

 

 

No, that was Fred I, Wingnuts truck. He has either the 4.8 or the 5.3 now.

[Darkanion]

No, that was Fred I, Wingnuts truck. He has either the 4.8 or the 5.3 now.

 

I think it's the 4.8, then... He was talking about doing work on it a while back, to make it stronger, for the drags..

[Zembonez]

Mine is a 4.8. It has great power beyond about 20MPH, but the crappy 3.23s are most of the issue there I believe. I'm gonna see what the gear change does first. The rest of my parts should hit here on Tuesday.

 

One of the nice things about the RCSB is the lighter weight.

[jrrod2004]

Thats interesting. I have the 4.8 but mine is the crew with the 3.23s out back. When I had it retuned, it woke up. The 4.8s that I have driven like to rev (I guess that is a characteristic) vs the 5.3. What I mean by this is when I rev to 5000, it takes its time dropping back down to idle whereas the 5.3 drops almost like a rock. As for the launches, the retune helped out especially with the shift points being moved to match the output of the engine... I wonder what yours will do with the regear.

[Wingnut]

Fred screams through first like shit through a goose, then at 5500 RPMS (+/-) it falls on it's face like a two year old on a skateboard and goes to 3,000 RPMS.

 

 

Jim...After your gears, I'd say do the Corvette kit and a tune...It'll feel like a whole different truck.

 

Oh...And yeah, your tuner CAN make WOT shifts different. Hell, I think you can have two completely different tunes...That you can switch between by hitting the tow/haul button....But I've never had that, and I could be making it up completely. You'll have to ask a tuner aboot that specifically I'd guess.

[Stevens03]

I had my 5.3 shifting at 6000 rpm and 40mph out of first. Seemed to work pretty nice. The diablo doesn't go that high on the vmax, but I think its around 5800 and 40mph. Both trucks had/have 4.10 gears.

[Mark_in_Tulsa]

Changing gears won't change where your shift points are. Now obviously putting in the 3.73 it will get there faster, but if you have had a tune done already, you won't need a re-tune for the new gears.

 

I don't know what RPM I shift at, but I know at 91-93 mph is when I hit 3rd at WOT with my custom tune.

I have 3.73. with a 5.3.