I have to be honest, prior to reading on this board i'd generally not even been aware that transmission fluid in an automatic would need changing... but then thats a habit inhereted from a father and cars didn't last as long in his day. So just like this site has opened my eyes about synthetics and better coolants and stuff, what is the distilled wisdom of changing transmission fluid in vehicles where it WASNT mentioned in the manual or even something to be aware of at the time? I'm wondering if all those things I heard about engine oil, especially 'clouding points' in cold climates and similar if it applies the same to/degrades transmission fluid in similar fashion... possibly meaning different recommendations for yearly freezing climates vs warmer ones too.
Like i've got two old Chevy vehicles (a caprice and a pickup, tho very few miles on the pickup) 1990 and 1991 with the same TH700R4 in them. I'm not even sure if either were made to have fluid changed, and I wouldn't be surprised if the original 27 year old now fluid is still in each - i'm 95% sure it is because it hasn't leaked.
I'm wondering whether driving with that fluid is in any way 'bad' or if it's definately worth the effort to drop a pan and mess about with it - and how much of a priority that should be. (since i'm trying to just get either of the vehicles up and running again, after multiple years of unfortunate sitting due to a TBI fuel problem in each, and i've spent my discretionary income on a car I screwed up meant to be a daily driver so it's down to emergency cash only until I can work it off in 6 months) Like could it wait until spring if it should be done, or does it need to be done at all, or am I damaging the vehicle slowly with every drive like a fool if I dont...
Yet i'm more curious on just what are the generally recommended principles? The above are just examples... instead of asking for every other car in the future, i'm curious what Best Practices should be for vehicles with no recommended interval, or for whom changing it might even be a PITA/not designed for by factory to do.
Like i've got two old Chevy vehicles (a caprice and a pickup, tho very few miles on the pickup) 1990 and 1991 with the same TH700R4 in them. I'm not even sure if either were made to have fluid changed, and I wouldn't be surprised if the original 27 year old now fluid is still in each - i'm 95% sure it is because it hasn't leaked.
I'm wondering whether driving with that fluid is in any way 'bad' or if it's definately worth the effort to drop a pan and mess about with it - and how much of a priority that should be. (since i'm trying to just get either of the vehicles up and running again, after multiple years of unfortunate sitting due to a TBI fuel problem in each, and i've spent my discretionary income on a car I screwed up meant to be a daily driver so it's down to emergency cash only until I can work it off in 6 months) Like could it wait until spring if it should be done, or does it need to be done at all, or am I damaging the vehicle slowly with every drive like a fool if I dont...
Yet i'm more curious on just what are the generally recommended principles? The above are just examples... instead of asking for every other car in the future, i'm curious what Best Practices should be for vehicles with no recommended interval, or for whom changing it might even be a PITA/not designed for by factory to do.
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