My wife drives an '01 Caddy Deville DHS that recently had the transmission replaced under an extended warranty (good experience BTW), I had been doing drain and refill with Valvoline Mercon V since that fluid also met the old Dex III spec from when the trans was new. The dealer put in a used transmission and flushed/refilled it with Dex IV. Can I still do my maintenance with the Valvoline Merc V? My Jagaur also uses this fluid so it means I only ahve to have one fluid on hand. Are Dex IV and Merc V incompatible in this since or is it "OK" since they both meet the old Dex III spec?
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Dex IV and Mercon V in Older Caddy?
- Thread starter UncleRunkle
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UncleRunkle
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My bad Whitewolf you are indeed correct Dex VI is what I meant. I know that GM back-spec'd the trans for Dex VI, but I was actually running Valvoline Full Synthetic Mercon V (older formulation) in it, because it met the Dex III spec that the car had originally. My question is when I service the trans (via a B&M drain plug installed in the pan) with a drain and fill, can I mix Mercon V and Dex VI?
The Jag is an '01 S-type with a 5r55n 5 speed trans.
The Jag is an '01 S-type with a 5r55n 5 speed trans.
You can if you get a multi-functional amazing fluid like Amsoil~
On a real note, many people swapped different types of fluids in the old day's to gain certain properties they wanted in the types of transmission fluids. I feel if the fluid has a backward spec to the fluid you should be running. It's ok! Other wise...A Mercon V really should be not used in a Dex III spec.
But, in the old day's many folks used Ford type fluids in GM type transmissions to gain certain positive functions. Like, Shifting etc... I can't really answer your questions just give you information and the choice is yours. Anyone else?
On a real note, many people swapped different types of fluids in the old day's to gain certain properties they wanted in the types of transmission fluids. I feel if the fluid has a backward spec to the fluid you should be running. It's ok! Other wise...A Mercon V really should be not used in a Dex III spec.
But, in the old day's many folks used Ford type fluids in GM type transmissions to gain certain positive functions. Like, Shifting etc... I can't really answer your questions just give you information and the choice is yours. Anyone else?
I've used Ford Type F in the built Turbo 400 in my '68 Buick Gran Sport, on the recommendation of the transmission builder, since 1978 and it works exactly the way I want it.
Having said that, I wouldn't use Mercon V in a modern GM product. Today's electronically-controlled transmissions are much more sensitive to the fluid recipe. I'd use Dex-VI.
Having said that, I wouldn't use Mercon V in a modern GM product. Today's electronically-controlled transmissions are much more sensitive to the fluid recipe. I'd use Dex-VI.
UncleRunkle
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OK, let me start all over again.
The only question I have is: Can Mercon V and DEXRON VI be mixed in a trans that would live happily with DEXRON III (a spec both fluids meet easily, no one should argue this point) without massive additive clash?
The only question I have is: Can Mercon V and DEXRON VI be mixed in a trans that would live happily with DEXRON III (a spec both fluids meet easily, no one should argue this point) without massive additive clash?
I suppose it will work just as well as it did before. Why did it need a new transmission?
I'd keep using Dex VI if I were you, it is a good fluid.
I'm sure the mixing isn't that big of a deal since if you hadn't needed to get a transmission replacement you'd have a 4T80E trans (I believe) with DexIII/Mercon V in it. If you asked if you could do a drain and refill with Dex VI we'd all say sure, go ahead, you'd be using the correct fluid and your older fluid was also the correct fluid back when it was made.
What trans do you have in your Jag? If it is an older one with a GM trans perhaps you could just switch it over to Dex VI also? Or does it spec. Mercon V? I don't know what newer Jag's use for transmissions.
I'd keep using Dex VI if I were you, it is a good fluid.
I'm sure the mixing isn't that big of a deal since if you hadn't needed to get a transmission replacement you'd have a 4T80E trans (I believe) with DexIII/Mercon V in it. If you asked if you could do a drain and refill with Dex VI we'd all say sure, go ahead, you'd be using the correct fluid and your older fluid was also the correct fluid back when it was made.
What trans do you have in your Jag? If it is an older one with a GM trans perhaps you could just switch it over to Dex VI also? Or does it spec. Mercon V? I don't know what newer Jag's use for transmissions.
UncleRunkle
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The 01 S-type uses a Ford 5R55N 5-speed automatic (very similar to the 5 speed autos found in V8 Explorers). My Jag specs Mercon V in both trans and power steering. 03 and up S-types use the Borg wagner 6 speed auto and it has it's own "super special" fluid.
Why would you want to use their product again if your transmission went out while using it. I've had recent problems with my Corolla after using Valvoline dex/merc and after seeing this I'll never mess with any of their fluids again.
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UncleRunkle
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Originally Posted By: brian12
Why would you want to use their product again if your transmission went out while using it. I've had recent problems with my Corolla after using Valvoline dex/merc and after seeing this I'll never mess with any of their fluids again.
The failure was not fluid related.
Why would you want to use their product again if your transmission went out while using it. I've had recent problems with my Corolla after using Valvoline dex/merc and after seeing this I'll never mess with any of their fluids again.
The failure was not fluid related.
Probably mixing the fluids will do no harm, but why mix? Dexron-VI is a 100,000 mile fluid. In any case, it is little trouble to get some Dex-VI when you need it...and you probably won't.
Most extended service plans expire at 100k miles. Why did that Caddy need a new transmission? It should not have needed the transmission nor should you have the need to buy the extended service plan. Poor GM...they probably deserve to fail, although I sure don't want those workers, and the workers of the suppliers, out of a job.
Most extended service plans expire at 100k miles. Why did that Caddy need a new transmission? It should not have needed the transmission nor should you have the need to buy the extended service plan. Poor GM...they probably deserve to fail, although I sure don't want those workers, and the workers of the suppliers, out of a job.
Originally Posted By: Ken2
Probably mixing the fluids will do no harm, but why mix? Dexron-VI is a 100,000 mile fluid. In any case, it is little trouble to get some Dex-VI when you need it...and you probably won't.
Most extended service plans expire at 100k miles. Why did that Caddy need a new transmission? It should not have needed the transmission nor should you have the need to buy the extended service plan. Poor GM...they probably deserve to fail, although I sure don't want those workers, and the workers of the suppliers, out of a job.
I agree they deserve to go under. Even after the government gives them all that money they will just be broke again in another five or ten years because they can't run a business. [censored] products and [censored] service.
Probably mixing the fluids will do no harm, but why mix? Dexron-VI is a 100,000 mile fluid. In any case, it is little trouble to get some Dex-VI when you need it...and you probably won't.
Most extended service plans expire at 100k miles. Why did that Caddy need a new transmission? It should not have needed the transmission nor should you have the need to buy the extended service plan. Poor GM...they probably deserve to fail, although I sure don't want those workers, and the workers of the suppliers, out of a job.
I agree they deserve to go under. Even after the government gives them all that money they will just be broke again in another five or ten years because they can't run a business. [censored] products and [censored] service.
Yes, you can use the MerconV for your maintenance intervals. But, I'd put my money on the DexronVI for the Jaguar.
GM won't go under. They are simply trying to break the union. Mismanage the company into bankruptcy, then reorganize with no union.
GM won't go under. They are simply trying to break the union. Mismanage the company into bankruptcy, then reorganize with no union.
Originally Posted By: unDummy
GM won't go under. They are simply trying to break the union. Mismanage the company into bankruptcy, then reorganize with no union.
I wish them luck!
GM won't go under. They are simply trying to break the union. Mismanage the company into bankruptcy, then reorganize with no union.
I wish them luck!
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