I have a 2006 Grand Prix GXP with the V8 and the under hood temps get very hot. The car has a trans temp gauge from factory and I can usually keep thew fluid under 200F with my trans cooler that I installed at my last transmission fluid change at 40,000 miles. The car now has almost 70,000 miles, the transmission fluid still looks super clean and not burnt at all. What is the recommened miles of dex VI?
When should I change my trans fluid
- Thread starter dan_erickson
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FYI, my experience with Dexron VI may not be typical. I change(drain and fill, not power flush) transmission fluid in my 95 bmw 525i with 188,000 miles about every 30,000 miles. We also blow ari through the transmission oil cooler to get more fluid exchanged.
This is a GM french made transmission known to be a bit failure prone. Go figure??
The past 3 fills were, Mobil 1 synthetic, Castrol Dexron VI and currently use Valvoline Dexron VI. At 30,000 the Castrol Dexron VI looked fine. I except the Valvoline to be even better since it is supposed to be full sytnthetic?? We shall see.
IMO, the key here is regular service. Do not ignore on any transmission regardless of so called lifetime or extended fills.
This is a GM french made transmission known to be a bit failure prone. Go figure??
The past 3 fills were, Mobil 1 synthetic, Castrol Dexron VI and currently use Valvoline Dexron VI. At 30,000 the Castrol Dexron VI looked fine. I except the Valvoline to be even better since it is supposed to be full sytnthetic?? We shall see.
IMO, the key here is regular service. Do not ignore on any transmission regardless of so called lifetime or extended fills.
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More often the better. Fluid is cheap, a magnefine would help a lot too.
Kestas
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Someone once posted the transmission fluid life versus operating temperature. This was for regular, nonsynthetic fluid.
Temp...Life
175....100K
195.....50K
220.....25K (common operating temp for most vehicles)
240.....10K
260......5K
300......1K
Dex VI has twice the life of Dex III. I'd say you have little to worry about your fluid. But there are always mitigating factors to the chart above, such as accuracy of the gauge and the number of shift events you have (city vs highway driving). Plus, the fluid can get loaded with contaminants and clutch material, even though it isn't oxidised.
I'd still err on the side of caution and change it earlier than specified.
Temp...Life
175....100K
195.....50K
220.....25K (common operating temp for most vehicles)
240.....10K
260......5K
300......1K
Dex VI has twice the life of Dex III. I'd say you have little to worry about your fluid. But there are always mitigating factors to the chart above, such as accuracy of the gauge and the number of shift events you have (city vs highway driving). Plus, the fluid can get loaded with contaminants and clutch material, even though it isn't oxidised.
I'd still err on the side of caution and change it earlier than specified.
I'd change half of it for insurance. Is that the Northstar or the 5.3 V8? Either way, the 4T65-HD behind it doesn't like coping with just a supercharged 3800 V6's 240 hp/280 ft-lbs. With a more powerful V8, it's even rougher on the transmission. That's why I'd drain the pan and refill with new.
Kestas, the OEM ATF on my fiancee's 09 Honda was well-cooked after 20k miles. I'd guess it sees over 200*F regularly.
Kestas, the OEM ATF on my fiancee's 09 Honda was well-cooked after 20k miles. I'd guess it sees over 200*F regularly.
Yup yup. I know all about the 4T65E-HD and how it kinda sucks lol. I have the 5.3L V8 with 303 HP and 326 of torque and I drive the car hard. It sees WOT to 100 at least three times and week, couple drag races at the stip a year just for fun and I even did an auto X event this spring.
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Originally Posted By: Kestas
Someone once posted the transmission fluid life versus operating temperature. This was for regular, nonsynthetic fluid.
Temp...Life
175....100K
195.....50K
220.....25K (common operating temp for most vehicles)
240.....10K
260......5K
300......1K
Dex VI has twice the life of Dex III. I'd say you have little to worry about your fluid. But there are always mitigating factors to the chart above, such as accuracy of the gauge and the number of shift events you have (city vs highway driving). Plus, the fluid can get loaded with contaminants and clutch material, even though it isn't oxidised.
I'd still err on the side of caution and change it earlier than specified.
I can't even get my temps above 180...... And that's driving the *insert choice expletive here* out of it......
Someone once posted the transmission fluid life versus operating temperature. This was for regular, nonsynthetic fluid.
Temp...Life
175....100K
195.....50K
220.....25K (common operating temp for most vehicles)
240.....10K
260......5K
300......1K
Dex VI has twice the life of Dex III. I'd say you have little to worry about your fluid. But there are always mitigating factors to the chart above, such as accuracy of the gauge and the number of shift events you have (city vs highway driving). Plus, the fluid can get loaded with contaminants and clutch material, even though it isn't oxidised.
I'd still err on the side of caution and change it earlier than specified.
I can't even get my temps above 180...... And that's driving the *insert choice expletive here* out of it......
Originally Posted By: sciphi
I'd change half of it for insurance. Is that the Northstar or the 5.3 V8? Either way, the 4T65-HD behind it doesn't like coping with just a supercharged 3800 V6's 240 hp/280 ft-lbs. With a more powerful V8, it's even rougher on the transmission. That's why I'd drain the pan and refill with new.
Kestas, the OEM ATF on my fiancee's 09 Honda was well-cooked after 20k miles. I'd guess it sees over 200*F regularly.
No it's a LS4 with a modified crankshaft to fit transversely. It also has LS6 heads stock. The Bonneville GXP did have Northstar for a couple of years. I think they used the 4T80 though (in the Bonneville, even though it's not a Cadillac.)
I'd change half of it for insurance. Is that the Northstar or the 5.3 V8? Either way, the 4T65-HD behind it doesn't like coping with just a supercharged 3800 V6's 240 hp/280 ft-lbs. With a more powerful V8, it's even rougher on the transmission. That's why I'd drain the pan and refill with new.
Kestas, the OEM ATF on my fiancee's 09 Honda was well-cooked after 20k miles. I'd guess it sees over 200*F regularly.
No it's a LS4 with a modified crankshaft to fit transversely. It also has LS6 heads stock. The Bonneville GXP did have Northstar for a couple of years. I think they used the 4T80 though (in the Bonneville, even though it's not a Cadillac.)
If you have not added filtration such as a magnefine in the cooler line somewhere, then it would be a good idea to change the fluid again at 100k miles. Otherwise, with the extra cooler AND filtration, I think that a 100k miles change interval would be fine, depending on how the fluid looks and smells. I say this, assuming you are talking about a complete flush when you say fluid change...not just a pan drop and refill, which only replaces half the fluid or thereabouts. Also, If you beat the tar out of it regularly, then a more frequent service interval would be recommended.
Originally Posted By: bmwtechguy
If you have not added filtration such as a magnefine in the cooler line somewhere, then it would be a good idea to change the fluid again at 100k miles. Otherwise, with the extra cooler AND filtration, I think that a 100k miles change interval would be fine, depending on how the fluid looks and smells. I say this, assuming you are talking about a complete flush when you say fluid change...not just a pan drop and refill, which only replaces half the fluid or thereabouts. Also, If you beat the tar out of it regularly, then a more frequent service interval would be recommended.
I am talking about doing a pan drop and filter change, that replaces 8 of the 12 quarts that the trans holds.
If you have not added filtration such as a magnefine in the cooler line somewhere, then it would be a good idea to change the fluid again at 100k miles. Otherwise, with the extra cooler AND filtration, I think that a 100k miles change interval would be fine, depending on how the fluid looks and smells. I say this, assuming you are talking about a complete flush when you say fluid change...not just a pan drop and refill, which only replaces half the fluid or thereabouts. Also, If you beat the tar out of it regularly, then a more frequent service interval would be recommended.
I am talking about doing a pan drop and filter change, that replaces 8 of the 12 quarts that the trans holds.
A $7 hand pump makes the job easier. Otherwise you have ATF all over. I wised up after the first pan drop on my 1999 Buick's 4T65. Plus you can get a transmission cooler install kit for $10 that has the right hose fittings. Then you can do a full flush very easily.
I'd get full-synthetic Dex-VI or Maxlife ATF. Change intervals would be 40-50k miles.
I'd get full-synthetic Dex-VI or Maxlife ATF. Change intervals would be 40-50k miles.
I went ahead and dropped the trans pan with only 30,000 miles on Dex V1 to find this..... not good. I am still under extened warranty so I hope this gets taken care of
Did you tow the car in, right then and there?
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