Dex/Merc-III with Lubeguard red vs Mercon V

[T-Stick]

For the 4R100 transmission in a 7.3 Powerstroke, which option do you think would offer the best protection when following the prescribed 30k service interval?

1. a current Dex/Merc-III (Valvoline/Castrol/Chevron)with Lubeguard red
2. a mercon V fluid

 

[buck91]

Originally specd or back specd for mercon v? Ive had good results both ways in an AODE. Ran napa dex/merc without additives in a 99 F250 also.

 

[T-Stick]

I'm talking the current back-speced mercon V.

I also currently run Napa Dex/Merc and Lubeguard red with good shifting.

 

[RF Overlord]

Since Lubegard is one of the few "mechanic-in-a-can" products that is not snake oil, I would have to say that either method would work fine, but I would personally use Mercon V*...why buy and have to deal with two separate products when one will do?

*...assuming Ford had approved Mercon V for the 4R100.

 

[SwampSurvivor]

Mercon V is specified for the 4R100 ... at least in in the owner's manual of my father's 2001 F350.

 

[T-Stick]

Mercon V was not originally spec'ed for the 4R100--in fact you were instructed not to use it. Mercon V was reformulated for the 4R100 and the original Mercon V transmissions. The most particular spec is still the old De/Merc III formulations even though Mercon is no longer licensed by Ford. Some owners still report better results with the Dex/Merc III formulations than the new Mercon V.

Some R100 owners add Lube Guard to address issues with Mercon V and some people report no issues with Mercon V.

I was thinking more along the lines of following the original specification for the 4R100 and then upgrading its performance with Lubeguard. Currently this is what I'm doing. The Mercon V has more friction modifiers which may shorten the life of the clutches.

 

[qdeezie]

Here's my .02.

The E4OD/4R100 transmissions are indeed picky when it comes to ATF.

My experience has been that they run well with Valvoline/Castrol products. I would imagine the Napa brand falls under the Valvoline umbrella.

I use Valvoline Maxlife ATF in my E4OD. Prior to that, I tried using cheap ATF (twice) and it shifted erratically. After putting Maxlife in my transmission, it shifted silky smooth.

My take on it is if you use a Valvoline or Castrol product (or a good name brand product), you won't need to add Lubegard.

I think Lubegard in this scenario would be necessary if you went economy class with your ATF.

The safest route would be to buy Motorcraft Mercon V if you're really concerned with the fluid you're using.

Basically what I'm getting at is that brand matters in these transmissions. As for which brands, you'll have to see what others have done in the past and what results they've gotten.

 

[ford46guy]

I would say Mercon V (if that what is on the chart). Here is my reasoning- Ford does not want to pay for warranty claims, so I go by what they say, especially if the advice is a few years old.
You can't go wrong with quality MV if its Ford approved for your application. The additives are for the quick lube places that keep one fluid for all cars. The dealer MUST use what ford suggests, no matter what the age of the car. If the oil goes for analysis and it is determined something else is used, and there is a failure, there could be liability on the part of the dealership. You could also add lubeguard to MV, I've done and have over 50K miles on some very high mileage trans. Lubeguard is one additive that could be used as a preventative, but it is still optional. I know a trans builder here that puts a bottle in at every service and rebuild.

 

[SwampSurvivor]

That's interesting - just checked online and the printing just mentions Mercon ... doesn't say V or otherwise

 

[Greasymechtech]

https://www.fcsdchemicalsandlubricants.com/main/quickref.asp

I'd use merconv over a conventional dexron. Lubegard Red can still be used.

 

[T-Stick]

Let me approach this from another angle. There is a difference between the Mercon spec and the reformulated Mercon V spec because companies like Valvoline still make both. Further proof is also that you cannot use the current Mercon V ATF in a transfer case that was designed for Mercon ATF.

I still wonder whether the additional friction modifiers required in the Mercon V spec are not detrimental clutches over a longer period of time. Ford did not come out with the Mercon V spec till most of their Mercon spec'ed vehicles were out of warranty and most of the original 4R100s were already needing a rebuild.

My intent is not to be cheap but to have the right lubricity spec. for the clutches. Amsoil's Torq Drive ATF is an expensive synthetic ATF that is designed to meet the Allison and the original Mercon spec by not having friction modifiers in it.

This is why I'm wondering whether the addition of Lubeguard red will not give some of the benefits of a synthetic or Mercon V ATF while still retaining the optimum lubricity for the clutches.

My current usage of NAPA/Valvoline Mercon with Lubeguard red really gives a nice balance of smooth yet firm shifting. I like the idea of using a premium synthetic ATF but I don't want to sacrifice longevity. I currently have a large 6.0 cooler on the truck and an inline magnefine filter on the return line. I have a drain plug on the pan so I do one drain/refill once a year so the fluid stays relatively stable.

 

[T-Stick]

Here is another way of looking at it. Allison continued their spec which is built around the Mercon/Dexron III when Ford and GM discontinued theirs. The Allison spec was upgraded also from TES 389 (Dexron III) to TES 295 for longer service life. Their spec is closer to the original Mercon applications than Mercon V because they also minimize friction modifiers. This still leads me to believe the Mercon V spec is not the best fit for the 4R100 but rather a compromise spec.

References:
http://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/9C10295EDD368D3680257AA900531905/$File/Castrol_Transynd_2710.pdf

http://www.allisontransmission.com/parts-service/approved-fluids/on-highway-fluids

http://www.allisontransmission.com/parts-service/approved-fluids/on-highway-fluids