I replaced the oil cooler and then about a month later, the low coolant light appeared again and sure enough it registers low in the resavior. The car has never overheated or registered high. What do I do now? Thanks
Put more coolant in. Continue to monitor the loss. A few pints in a month is not heavy enough to show a significant leak.
Add coolant to the correct level and monitor it. Can you see a leak anywhere? Are there any spots on the ground under the car?