4l60E RPM Question

[Rock Surf]

I have a new to me 2003 Yukon SLT 4x4. It's has 225k, but has had a remanu tranny put in about 1 1/2 yrs ago.

1st through 4th shift smoothly.

My question is, Is it normal for it to be just above 2k in 4th @ 65mph?

It seems like the ratio between 3rd and 4th should be larger. I keep anticipating that phantom gear change at 65mph to 70mph that i know is not there because I'm already in 4th.

 

[Fless]

Would help to know the diff ratio. Has it been determined from your RPO build codes in the glovebox?

 

[Rock Surf]

Would help to know the diff ratio. Has it been determined from your RPO build codes in the glovebox?

3.73

To rephrase the question :

"Does your 5.3 4L60E with 3.73 gears run at 2k to 2500 rpm, @ 65mph to 70mph in 4th gear?"

 

[M1Gunner]

My rpms sit around that and I’m on 37’s rollin 5.13 gears. Well, when I’m runnin 75 on the highway I’m right dead nuts at 2k.

 

[#1taho]

3.73

To rephrase the question :

"Does your 5.3 4L60E with 3.73 gears run at 2k to 2500 rpm, @ 65mph to 70mph in 4th gear?"

Mine is about 2200 rpm at 65-70mph. Seems normal to me

 

[rockola1971]

Tire size also comes into play here along with rearend ratio. Sounds normal to me. What on earth are you talking about with the "phantom gear change"? You should be shifting into 4th (OD) around 45-50mph at normal throttle.

 

[Rock Surf]

Tire size also comes into play here along with rearend ratio. Sounds normal to me. What on earth are you talking about with the "phantom gear change"? You should be shifting into 4th (OD) around 45-50mph at normal throttle.

Thanks for the replies guys. Sounds like its normal.

By phantom gear change, I just mean that I'm anticipating another gear change because of the RPM and engine sound in 4th gear at 70mph. Seems a bit odd that it doesn't shift to below 2k at 70mph. I'm still getting to know the truck and it's nuances.

 

[#1taho]

I think almost all trucks and car that's are not sports car run about 2000rpm at 70mph.
My new ford is the same.

 

[dmperfection101]

Sounds right to me. I'm at 2000 to 2200 at 64 to 70 mph

Sent from my SM-G955U using Tapatalk

 

[Chubbs]

I have a new to me 2003 Yukon SLT 4x4.

My question is, Is it normal for it to be just above 2k in 4th @ 65mph?

I have the exact same truck, down to the 3.73 g/r. just bought it back in April.

RpMs are correct.

You need to pump out your old transmission fluid via the cooler return line. Remove the pan, replace the filter & seal and bolt the pan back on with a new gasket. You can buy a kit with everything required for under $20.

Now refill it with AC Delco Dexron6 synthetic @ the fill tube.

After you do that, flush the power steering system with a can of sea foam TransTune & a cheap quart of PS fluid. After you work that through the pump & cooler real well, drain& refill with a can of Lucas PS conditioner and quart of GM approved synthetic PS fluid. Pump must have fluid circulating at all times, never allow it to run dry

This only puts you about 20% of the maintenance checklist but these 2 are the doozies. Gotta get new fluids & filters in your setup @ this mileage. You will find an external fuel filter on VIN-z flex engines that creates a resistance from contaminants which burns up the fuel pump. You want the NAPA Gold replacement. Replace spark plugs & wires. Flush the coolant and examine the clutch fan for proper operation.

I would bet that both of the differentials are operating in black goop (75/90 syn in the rear, 80wt convent in front) & replace the TC fluid with the blue AutoTrak2. Look over the tailshaft housing of TC for pinhole leaks caused by the pump-rub syndrome. You have to pop the diff cover on back axle to drain, NAPA sells the primo blue FelPro gasket to reseal it.

I went with the AC Delco 5w30 dexos (6qts) & Delco filter in the motor. Don't forget the $1 PCV valve and inspect the brakes, steering linkage.

Document all of the work In owners manual & pack all of the receipts in there.