GLK250 Shift Points
07-22-2014, 10:25 PM
#1
Member
Thread Starter
GLK250 Shift Points
Just curious-
I know my T1N Sprinter and GLK250 are far different animals, but the 4cyl GLK250 seems to up shift so much later rpm wise under very light acceleration than the 5cyl Sprinter, which up shifts at only 1800-1900rpm under similar acceleration.
I get great mileage in the GLK- 30-38 mpg, so, so it's not spoiling the economy.
What is considered normal for the GLK250?
I know my T1N Sprinter and GLK250 are far different animals, but the 4cyl GLK250 seems to up shift so much later rpm wise under very light acceleration than the 5cyl Sprinter, which up shifts at only 1800-1900rpm under similar acceleration.
I get great mileage in the GLK- 30-38 mpg, so, so it's not spoiling the economy.
What is considered normal for the GLK250?
07-23-2014, 03:10 AM
#2
Junior Member
Mine seems to upshift anywhere between 1800-2200 when driving in school zones etc.
Consider this. Max torque is in 1600-1800 range. Redline is at 5200 rpm. In sport mode all upshifts are at 4500 rpm. Also the automatic transmission will not let you drive it at high or low rpms for too long. Imo, shifting befeore 2500 rpm will give you good efficiency with good dynamic.
Also, sprinters OM612 engine has a very wide torque bend, from 1400rpm to 2400 rpm.
Consider this. Max torque is in 1600-1800 range. Redline is at 5200 rpm. In sport mode all upshifts are at 4500 rpm. Also the automatic transmission will not let you drive it at high or low rpms for too long. Imo, shifting befeore 2500 rpm will give you good efficiency with good dynamic.
Also, sprinters OM612 engine has a very wide torque bend, from 1400rpm to 2400 rpm.
07-23-2014, 03:09 PM
#3
Member
Thread Starter
Mine seems to upshift anywhere between 1800-2200 when driving in school zones etc.
That's more of what I was expecting for that kind of driving (good description), but my 2500rpm seems high for such light throttle position.
Consider this. Max torque is in 1600-1800 range. Redline is at 5200 rpm. In sport mode all upshifts are at 4500 rpm. Also the automatic transmission will not let you drive it at high or low rpms for too long. Imo, shifting befeore 2500 rpm will give you good efficiency with good dynamic.
Yes, I was expecting it to drop into the next gear in the low end of that range at minimal throttle.
Also, sprinters OM612 engine has a very wide torque bend, from 1400rpm to 2400 rpm.
Yes, different design and computer calibration. I guess I've gotten used to seldom seeing more than 2200rpm in any gear except 5th at highway speeds, or when I tow a trailer, so min shift points at 2500 in this vehicle got my attention.
The torque converter didn't like to disengage when I got the vehicle (new), but the dealer said it was normal, but finally it would NOT unlock at all, and would slip the clutch packs, and finally stall the engine coming to a stop, at which point the dealer finally agreed to look at it, and after a month waiting for authorization and parts, changed the torque converter.
I asked the service manager to ride with me to see if the shift points seemed OK, but he wouldn't, saying it wouldn't ever leave the shop if it wasn't within specifications in the first place.
I wanted to check here to make sure nothing had happened to the transmission itself from the defective TC, causing such late shifts at exceptionally light throttle. Under moderate/heavy acceleration it shifts about where I'd have suspected, however.
That's more of what I was expecting for that kind of driving (good description), but my 2500rpm seems high for such light throttle position.
Consider this. Max torque is in 1600-1800 range. Redline is at 5200 rpm. In sport mode all upshifts are at 4500 rpm. Also the automatic transmission will not let you drive it at high or low rpms for too long. Imo, shifting befeore 2500 rpm will give you good efficiency with good dynamic.
Yes, I was expecting it to drop into the next gear in the low end of that range at minimal throttle.
Also, sprinters OM612 engine has a very wide torque bend, from 1400rpm to 2400 rpm.
Yes, different design and computer calibration. I guess I've gotten used to seldom seeing more than 2200rpm in any gear except 5th at highway speeds, or when I tow a trailer, so min shift points at 2500 in this vehicle got my attention.
The torque converter didn't like to disengage when I got the vehicle (new), but the dealer said it was normal, but finally it would NOT unlock at all, and would slip the clutch packs, and finally stall the engine coming to a stop, at which point the dealer finally agreed to look at it, and after a month waiting for authorization and parts, changed the torque converter.
I asked the service manager to ride with me to see if the shift points seemed OK, but he wouldn't, saying it wouldn't ever leave the shop if it wasn't within specifications in the first place.
I wanted to check here to make sure nothing had happened to the transmission itself from the defective TC, causing such late shifts at exceptionally light throttle. Under moderate/heavy acceleration it shifts about where I'd have suspected, however.
Bob
Last edited by bobinyelm; 07-23-2014 at 03:14 PM.
