Problems with Lights on a 6.5L Diesel GMC

Volume 1 Issue 4 - 6.2/6.5 Issues and Answers

I have a question not related to my engine, but hope you can help. Our ’95 GMC has developed a variety of problems with its lights, while we were on a trip. The turn signals were sometimes dim and or they flashed rapidly. The brake lights often do not work at all and the tail lights are dim. All the lights are behaving oddly. A dealer checked it out for us and replaced many bulbs, but things are still goofy. He now says it needs a new turn signal switch at a cost of $620, but he will not guarantee this to be the fix. Do you have any suggestions?


Heating Problem After Replacing AC Pump

Volume 1 Issue 4 - 6.2/6.5 Issues and Answers

Our ’94 one-ton Chevy diesel seems to have a heating problem that we think began soon after we had the air conditioner pump replaced. The problem is, no one seems to be able to fix this for us. The temperature gauge goes up to 230ºF and back down; up and down it goes. It takes spells of swinging back and forth like this, then seems to be fine at other times. I am not convinced that it ever really gets hot, even when the gauge says it is. The mechanic at our dealership has replaced the thermostat, then the radiator, then the water pump, then the radiator hoses, then the temperature sensor, then the fan clutch and finally another new thermostat; all without solving the problem. After each visit, they tell me it is fixed and send me on my way with a lighter wallet, but the problem returns. Now, after all this expensive work has been done, we have noticed that the oil pressure gauge is reading lower than it used to and that the volt meter reads low. We also see that the speedometer jumps around when I rev the engine in neutral. Then, once in a while, the wipers will make an unplanned swipe across the windshield. Maybe I am being unfair to the mechanics, but none of these problems existed before the work was done. Understandably, I hesitate to take it back to the dealership for fear of the costs. Am I vexed? Can you offer help?


1998 Dually Smokes Like a Freight Train

Volume 1 Issue 4 - 6.2/6.5 Issues and Answers

Please help! We have a problem with our 1998 Chevy dually that has proven to be beyond the capability of mechanics, even so called diesel mechanics in our area. Our big red truck smokes like a freight train sometimes. It will be fine for a day or so then, when we need power most, it lets us down and only billows black smoke. So far, we have had to replace the turbocharger, catalytic converter thing, injectors, fuel filter and more – none of which fixed the problem. I am tired of trying to get results from people who seem to only be guessing; please help.


Country and Model Year from VIN

Volume 1 Issue 4 - 6.2/6.5 Issues and Answers

I have a question about the VIN (vehicle identification number) on the GM trucks. What character in the vin tells the country of manufacture? What character tells the year model?



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