Letting the truck idle in drive
#16
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Re: Letting the truck idle in drive
Originally posted by Cold Diesel
I am wondering if it hurts the tranny to let the truck idle in drive with the parking brake on? I am new to autos so I am not sure. I have been letting my truck idle in neutal to warm up before driving. EGT's in high idle are only 250*. When I put it in drive the EGT's are 425*. So I figure it will warn up faster that way. But will it hurt anything?
TIA
I am wondering if it hurts the tranny to let the truck idle in drive with the parking brake on? I am new to autos so I am not sure. I have been letting my truck idle in neutal to warm up before driving. EGT's in high idle are only 250*. When I put it in drive the EGT's are 425*. So I figure it will warn up faster that way. But will it hurt anything?
TIA
I read a post on another site that said IF you MUST leave it idle for very long, it is BETTER to have it in drive (with parking break set) because things don't get proper lubrication in neutral or park. The guy that made that post is a truck automatic transmission mechanic.
Bottom line is, I don't know what to believe.
#17
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Idling in drive is just not a safe thing to do from any standpoint when no one is in the truck.
Now I don't know about these funky new automatic transmissions but I can tell you that the old 727 Chrysler transmissions that were used in my 89 and the upgraded version of it that was used in my 95 definately did circulate the transmission fluid in neutral and not in Park. You could put the transmission in Park and the lines would cool off under the hood cause the fluid stopped circulating but a soon as you dropped it in neutral, the lines would heat up almost immediately cause the fluid was circulating again and cooling down. That's why when I drove auto's, I would always shift to neutral at lights and periods of idle time.
Now I don't know about these funky new automatic transmissions but I can tell you that the old 727 Chrysler transmissions that were used in my 89 and the upgraded version of it that was used in my 95 definately did circulate the transmission fluid in neutral and not in Park. You could put the transmission in Park and the lines would cool off under the hood cause the fluid stopped circulating but a soon as you dropped it in neutral, the lines would heat up almost immediately cause the fluid was circulating again and cooling down. That's why when I drove auto's, I would always shift to neutral at lights and periods of idle time.
#18
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Re: Letting the truck idle in drive
If your purpose is to warm the tranny. Then place it in neutral while idling. Neutral engages the pump and will then circulate the trans fluid. And yes, if your are getting a significant increase in temp with it in gear, there may well be a problem.
Originally posted by Cold Diesel
I am wondering if it hurts the tranny to let the truck idle in drive with the parking brake on? I am new to autos so I am not sure. I have been letting my truck idle in neutal to warm up before driving. EGT's in high idle are only 250*. When I put it in drive the EGT's are 425*. So I figure it will warn up faster that way. But will it hurt anything?
TIA
I am wondering if it hurts the tranny to let the truck idle in drive with the parking brake on? I am new to autos so I am not sure. I have been letting my truck idle in neutal to warm up before driving. EGT's in high idle are only 250*. When I put it in drive the EGT's are 425*. So I figure it will warn up faster that way. But will it hurt anything?
TIA
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