ZeeQuick Posted December 16, 2009 Report Posted December 16, 2009 My 99 Regal 3800 SC is pulling about 2500 rpms cruising at 65mph on the highway.....why does this not seem right to me? Quote
Andrew Posted December 16, 2009 Report Posted December 16, 2009 yeah that seems high. Maybe you lost OD or your TCC isnt locking up. Quote
ZeeQuick Posted December 16, 2009 Author Report Posted December 16, 2009 Well WTF? It seems to kick into OD when driving around a city speeds, just not on the highway. Checked the fluid, its fine. Quote
RobertISaar Posted December 16, 2009 Report Posted December 16, 2009 higher temps kicking it into default mode? Quote
ZeeQuick Posted December 16, 2009 Author Report Posted December 16, 2009 Any suggestions to troubleshoot this? It was fine a couple of days ago. I did change the thermostat and flush the heater core out yesterday, which has caused the car to run hotter (heat wasn't hot before). Don't see how that could be related. I did get on it a bit when entering the highway today right when I started to notice the issue... Quote
RobertISaar Posted December 16, 2009 Report Posted December 16, 2009 i can hear Crazy K typing away... Quote
cubsfan24 Posted December 16, 2009 Report Posted December 16, 2009 i can hear Crazy K typing away... I bet a transmission cooler would fix it Quote
xtremerevolution Posted December 16, 2009 Report Posted December 16, 2009 i can hear Crazy K typing away... I bet a transmission cooler would fix it He's in Ohio in December... If anything, his transmission might be too cold. Quote
ZeeQuick Posted December 16, 2009 Author Report Posted December 16, 2009 i can hear Crazy K typing away... I bet a transmission cooler would fix it He's in Ohio in December... If anything, his transmission might be too cold. Truth has been spoken! 20 degrees outside right now.... It will at times not go into OD when I first start driving and the motor is cold, but once it warms up its completely normal. I think I read something about the transmissions not engaging OD until the temp is over 100 degrees. If this was an issue with 4th gear, wouldn't it not go into OD at all speeds? Quote
RobertISaar Posted December 16, 2009 Report Posted December 16, 2009 the TCC won't lock until a certain temperature is reached, but it should changes gears normally... Quote
ZeeQuick Posted December 16, 2009 Author Report Posted December 16, 2009 Gears seem to change normally, you'll have to pardon my vagueness as its been about 10 years since I've had anything to do with an automatic transmission. I had noticed that the TCC didn't seem to be locking up as much as it was when I first bought the car during normal driving, but I passed it off as my imagination, or just not being familiar with the car, having only had it for a few weeks. Now with the TCC seemingly not locking up at all on the highway now, clearly there is a problem. Quote
xtremerevolution Posted December 16, 2009 Report Posted December 16, 2009 the TCC won't lock until a certain temperature is reached, but it should changes gears normally... Correct. More info: Both style sensors are negative temperature coefficient thermisters and both provide transaxle fluid temperature information to the PCM. The PCM sends a 5 volt reference signal to the sensors and measures the voltage drop in the circuit. The internal resistance of the sensors will drop as the operating temperatures of the transaxle fluid increase. The PCM then uses this information for determining when to engage or disengage the Torque Converter Clutch (TCC) or the Viscous Converter Clutch (VCC). The PCM inhibits TCC/VCC operation until transaxle fluid temperature reaches approximately 45°C (113°F). At this temperature, the PCM will allow the TCC/VCC to engage providing the throttle position, gear obtained, and other vehicle operating conditions are met. If transaxle fluid temperatures become excessively high, above approximately 130°C (266°F), the PCM will modify shift pattern and TCC schedules to reduce the temperature. If a situation occurs where a short or open is detected in the circuit, the PCM will store a code and use coolant temperature sensor information for transaxle temperature. Quote
tornado_735 Posted December 16, 2009 Report Posted December 16, 2009 At 65mph, I run 2000rpm on the nose (according to my tach) It has got to be stuck in third. Quote
Crazy K Posted December 16, 2009 Report Posted December 16, 2009 do you feel FOUR distinct shifts? 1-2 2-3 3-4 4-TCC lock up Quote
RobertISaar Posted December 16, 2009 Report Posted December 16, 2009 At 65mph, I run 2000rpm on the nose (according to my tach) you also have a 3.33 gear, whereas the L67s run at like 2.97/2.93, somewhere around there... Quote
ZeeQuick Posted December 16, 2009 Author Report Posted December 16, 2009 At what speed does OD usually kick in? Just driving around town at around 40mph, am I feeling the TCC lock up in 3rd gear and mistaking that for OD? Quote
RobertISaar Posted December 16, 2009 Report Posted December 16, 2009 with the 95 3100: if the shifter is left in D, it will lock eventually, can't remember where though. in OD, it will NOT lock in 3rd gear, but will shift to 4th, then lock at 45MPH. i imagine your setup MIGHT lock in 3rd. Quote
ZeeQuick Posted December 17, 2009 Author Report Posted December 17, 2009 Cruising at 50mph at very little throttle, if I drop it into 3rd from D, the tach does nothing, stays right at about 2000rpm. If I get on the freeway in 3rd and then drop it into drive at cruising speed, nothing happens. Is there anything that could be causing this besides 4th gear just being shot. The car runs absolutely perfect otherwise. Hell, if it didn't have a tach I probably never would have noticed. Quote
ZeeQuick Posted December 17, 2009 Author Report Posted December 17, 2009 Well after researching a bit I see that the 4 gear spline has a nice habit of shearing to the point where it is completely smooth. Awesome. Guess I'll get the car over to a mechanic that I know and see if we can manually engage fourth gear. If not, looks like it'll be time to bust out some $$$/ Quote
xtremerevolution Posted December 17, 2009 Report Posted December 17, 2009 Well after researching a bit I see that the 4 gear spline has a nice habit of shearing to the point where it is completely smooth. Awesome. Guess I'll get the car over to a mechanic that I know and see if we can manually engage fourth gear. If not, looks like it'll be time to bust out some $$$/ At this point I would consider the price of a transmission rebuild and compare that to the price of an L67 swap. I know if I have to pull my engine to fix the transmission, I'll just put in a low mileage L67 and be done with it. Quote
jeremy Posted December 17, 2009 Report Posted December 17, 2009 Well after researching a bit I see that the 4 gear spline has a nice habit of shearing to the point where it is completely smooth. Awesome. Guess I'll get the car over to a mechanic that I know and see if we can manually engage fourth gear. If not, looks like it'll be time to bust out some $$$/ At this point I would consider the price of a transmission rebuild and compare that to the price of an L67 swap. I know if I have to pull my engine to fix the transmission, I'll just put in a low mileage L67 and be done with it. his car already has the l67 Quote
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