ChuckVA
New Member
So, I was about to bring an older Mercon SP specs thread back to life with this info until I saw it devolved into two pages of bickering, and nobody looking for actual information is going to read past that. Better to start a new thread.
I've been digging into the specs and background on SP now that I'm the new owner of something with a 6R75, and finding out it's getting hard to get again. I had to hit two dealerships this week to get enough to do a torque converter swap locally (no time to order from Rock Auto), and both reported they're having trouble getting SP from national. I bought out my closest good dealership and got 2/3 of what I needed, and when they tried to order me a few more bottles, they ordered SP and their distributor threw more cases of LV on the truck instead, twice. My second reliable local dealership, an hour away, had enough on hand to finish the job but reported they've been having trouble getting it for a while. They order it and hoard it, but it's 50/50 on any given week whether they get any SP, or just get sent more LV like the first group.
The BMW and Jaguar guys that have this transmission have put a lot of effort into digging into this stuff, because the original ATF that Ford licensed for SP already cost upwards of $23 a quart from BMW and Jag dealerships a few years ago. They went looking for a lot of this info and found Mercon SP as their cheaper alternative, but the high price tag motivated a lot more digging than we've done when SP was easy to get here. Some of this also came from bobistheoilguy. I'm not going to source everything, a lot of this I gathered for my own notes and didn't save links for, so feel free to tell me I'm full of it and disbelieve everything, this is the internet.
First off, Ford doesn't manufacturer Mercon SP, that should be obvious. All Motorcraft fluids are manufactured under contract for Ford by someone else. Mercon SP was manufactured by Shell under Shell specification M1375.4. As far as I know, Shell is the only company to make the original fluid. It was not originally made for Ford, it was originally developed by Shell under contract to ZF specifically for the 6R family. Mercon SP is Shell M1375.4 with a Motorcraft sticker on it.
The equivalent you can buy for BMW/Jag, ZF Lifeguard Fluid 6, is the exact same ATF with another different sticker on it and twice the price. Shell also sold this for a while directly as Shell Spirax S4 ATF MSP, but isn't now as far as I can tell, and I don't see that anywhere for sale any more. But, if you can't get Mercon SP and absolutely want the original fluid, you can hit up a BMW dealership and pay twice the price to get the exact same thing.
Apparently what makes SP special is a lot of extra friction modifier. The formula is god knows what, they're always proprietary and guarded like the secret to eternal life, but think medium viscosity ATF with a bunch of extra Lubegard Shudder Fixx thrown in straight from the petroleum plant. Anecdotally somewhere I saw it mentioned that the SP actually stands for Shudder Proof, but I didn't really have a detailed source for that. Most likely the issue with using LV in these transmissions is that LV doesn't have enough friction modifier in it and causes shudder/chatter. From what I can see, in the later 6R80 it looks like they probably changed friction materials to clutches that match the usual Ford spec, so that's probably why the 80 gets along fine with normal Ford fluids.
The other important thing to know is that any ATF that lists itself as compatible with Shell M1375.4 is claiming to meet the Mercon SP spec, even if it doesn't say "Mercon SP". There are several that are easily available, many of which folks already know about - Valvoline MaxLife synthetic already claims M1375.4 compatibility, and I'm seeing more than a few people here run it. Castrol Transmax Full Synthetic Multi-Vehicle ATF also claims M1375.4, though I haven't seen that one mentioned on any Ford forums.
Given the choice I'll keep running the SP as long as I can get it, but if Ford stops contracting with Shell for it again I'm not paying BMW prices. We do more frequent ATF swaps due to a lot of towing, so if it gets hard to get, I might be giving the Valvoline a go at a future fluid change. Will just have to see.
Hopefully this is useful to someone looking for some of this info like I was last week.
I've been digging into the specs and background on SP now that I'm the new owner of something with a 6R75, and finding out it's getting hard to get again. I had to hit two dealerships this week to get enough to do a torque converter swap locally (no time to order from Rock Auto), and both reported they're having trouble getting SP from national. I bought out my closest good dealership and got 2/3 of what I needed, and when they tried to order me a few more bottles, they ordered SP and their distributor threw more cases of LV on the truck instead, twice. My second reliable local dealership, an hour away, had enough on hand to finish the job but reported they've been having trouble getting it for a while. They order it and hoard it, but it's 50/50 on any given week whether they get any SP, or just get sent more LV like the first group.
The BMW and Jaguar guys that have this transmission have put a lot of effort into digging into this stuff, because the original ATF that Ford licensed for SP already cost upwards of $23 a quart from BMW and Jag dealerships a few years ago. They went looking for a lot of this info and found Mercon SP as their cheaper alternative, but the high price tag motivated a lot more digging than we've done when SP was easy to get here. Some of this also came from bobistheoilguy. I'm not going to source everything, a lot of this I gathered for my own notes and didn't save links for, so feel free to tell me I'm full of it and disbelieve everything, this is the internet.
First off, Ford doesn't manufacturer Mercon SP, that should be obvious. All Motorcraft fluids are manufactured under contract for Ford by someone else. Mercon SP was manufactured by Shell under Shell specification M1375.4. As far as I know, Shell is the only company to make the original fluid. It was not originally made for Ford, it was originally developed by Shell under contract to ZF specifically for the 6R family. Mercon SP is Shell M1375.4 with a Motorcraft sticker on it.
The equivalent you can buy for BMW/Jag, ZF Lifeguard Fluid 6, is the exact same ATF with another different sticker on it and twice the price. Shell also sold this for a while directly as Shell Spirax S4 ATF MSP, but isn't now as far as I can tell, and I don't see that anywhere for sale any more. But, if you can't get Mercon SP and absolutely want the original fluid, you can hit up a BMW dealership and pay twice the price to get the exact same thing.
Apparently what makes SP special is a lot of extra friction modifier. The formula is god knows what, they're always proprietary and guarded like the secret to eternal life, but think medium viscosity ATF with a bunch of extra Lubegard Shudder Fixx thrown in straight from the petroleum plant. Anecdotally somewhere I saw it mentioned that the SP actually stands for Shudder Proof, but I didn't really have a detailed source for that. Most likely the issue with using LV in these transmissions is that LV doesn't have enough friction modifier in it and causes shudder/chatter. From what I can see, in the later 6R80 it looks like they probably changed friction materials to clutches that match the usual Ford spec, so that's probably why the 80 gets along fine with normal Ford fluids.
The other important thing to know is that any ATF that lists itself as compatible with Shell M1375.4 is claiming to meet the Mercon SP spec, even if it doesn't say "Mercon SP". There are several that are easily available, many of which folks already know about - Valvoline MaxLife synthetic already claims M1375.4 compatibility, and I'm seeing more than a few people here run it. Castrol Transmax Full Synthetic Multi-Vehicle ATF also claims M1375.4, though I haven't seen that one mentioned on any Ford forums.
Given the choice I'll keep running the SP as long as I can get it, but if Ford stops contracting with Shell for it again I'm not paying BMW prices. We do more frequent ATF swaps due to a lot of towing, so if it gets hard to get, I might be giving the Valvoline a go at a future fluid change. Will just have to see.
Hopefully this is useful to someone looking for some of this info like I was last week.
