Castrol TransMax or Valvoline Maxlife ATF

[NavyVet88]

Both of these fluids meet the specs for my 03 Buick century. It has 193k on the original transmission while the motor was just recently swapped and I want to keep it working for quite a few years to come.

Both fluids are literally 1 dollar difference from each other at Wal-Mart with my employee discount so cost is not much of a factor.

Which would you choose?

I also plan to drain and fill the trans at least 3 or 4 times to ensure I have mostly new fluid inside at the end. Also, how often after the first change do you recommend I drain and fill the fluid and swap the filters with the rest of the changes?

 

[Lubener]

Personally, I would go STech Dex 6 in a lower mileage unit but that's just me. In your case, I would go with the cheaper fluid, I don't think there would be a difference. The main thing is your changing it.I would do the initial pan drop/filter and then run it for a month and repeat. There is no good reason to do it again until around another 30k miles. There would be such a small percentage of old fluid left and the additive package would be robust. If you want an extra measure of protection, add a bottle of Lubeguard Red at the second pan drop. Check online, there are some inexpensive upgrades which will be beneficial to your 4T65E. A cooler would also help.

 

[RichardS]

I put Castrol trans HM in mine about 2 months ago with lubegard red, and so far so good. Going to run it for 20k, then dump again and likely add DexVI. I wanted the added detergency advertised in the HM incase there was any cleaning that needed to be done.

 

[Egg_Head]

I'm not certain which TransMax product you were considering. If it's the multi-vehicle Full Synthetic or DEX VI vs. Maxlife, they are all fine, go with the cheapest. I'd also suggest you get a Dorman transmission pan # 265-814 with a drain plug and replace that with your first drain and fill when you should be replacing your filter too. The Dorman pan will make future fluid replacements much easier.

According to Amsoil's website, your transmission has a total fluid capacity of 13.4 qts. and with a pan drop 7.4 qts. will be replaced. You may not get that much out using just the drain plug but here are your transmission fluid drain/refill replacement ratio calculations:

#1 55.22%
#2 77.95%
#3 91.02%
#4 95.98%
#5 98.20%
#6 99.19%
#7 99.64%

Happy Motoring!

 

[Lubener]

I was going to install that same Dorman pan. It was actually slightly shallower than the original and I read so many reviews about stubborn drain plug leaks so I returned it. It's not a big deal to drop the pan and make sure all debris is cleaned out off the magnet and pan bottom. One major problem contributor is small metallic particles finding their way to the solonoids. Much of that can be found on the pan bottom and once the magnet loads up, it won't attract that stuff much anymore.

 

[pbm]

I had a 2002 Century and I used Mobil 1 ATF when I changed the FF at 30K....I ran that M1 until 90K (I also put in a bottle of LG red and a couple of additional magnets). I refilled with the M1, LG red combo at 90K and the transmission was running great when I sold the car at 130K.

I know I'll get flamed for this but I don't like running the lower viscosity ATF's in vehicle's that weren't originally designed for them. I know that Dex. III thins out and Dex VI doesn't.....I base my opinion on the fact that my old Ford ZX2 didn't seem to like Maxlife (even though every other vehicle did). I do realize that the 4F-EAT transmission was known for a rough 1-2 shift....but thicker fluid seemed to help....

 

[NavyVet88]

Guys thank you so much for the info and advice on this! EggHead- I did find that Dorman pan with the drain plug on rock auto for about 20 bucks last night and I think I will give it a go. Also, I checked the stock last night at work and we are sold completely out of Maxlife and I asked the auto care manager when more would be in stock and he said we couldn't keep it on the shelf at all lately for some reason but we do have plenty of HM TransMax in stock.

 

[pbm]

The Castrol High Mileage ATF is a thick (8 Cst. @ 100*C) while the Maxlife is a thin ATF (under 6 Cst. @ 100*C)....I'd use a regular (formerly Dex 3) ATF in the 7 Cst. range...if you only have the 2 to choose from , I'd go with the Castrol in this application.

 

[Bgallagher]

Valvoline maxlife and a bottle of LGR is a great combo in most GM transmissions pre-Dex VI. Castrol makes some high quality ATFs but for a higher mileage vehicle like that I would use the maxlife.

 

[951Indy]

I've done 5 drain and fills using Maxlife and original trans still working fine at 351,000. I also drop the accumulator body and get a surprising amount of fluid from there.

 

[Linctex]

Originally Posted By: Lubener
One major problem contributor is small metallic particles finding their way to the solonoids. Much of that can be found on the pan bottom and once the magnet loads up, it won't attract that stuff much anymore.


Add more magnets

I have a spin-on transmission fluid filter on my F-150, and it has 6 magnets around the inlet holes. I plan to trap 99.99999% of all ferrous metals. Hopefully the filter (10 microns Baldwin) will get the rest.

 

[NavyVet88]

Is there a certain special place to put the magnets? Like a place where they would catch more of the metal fragments?

 

[Linctex]

Originally Posted By: NavyVet88
Is there a certain special place to put the magnets? Like a place where they would catch more of the metal fragments?


Anywhere where gravity helps (lowest part of the pan) and also where fluid flow is (like where fluid dumps out of the valve body)

 

[NavyVet88]

Gotcha

 

[zorobabel]

I would not put the magnets where full flow is. If the particles get magnetized and then dislodged from the magnet, who knows where they might stick afterwards.

 

[Linctex]

Originally Posted By: zorobabel
I would not put the magnets where full flow is. If the particles get magnetized and then dislodged from the magnet, who knows where they might stick afterwards.


I don't think you understand what I was saying.

Besides, what you propose doesn't actually ever happen.

 

[slacktide_bitog]

Out of those two, Maxlife, since it's a full synthetic (the Castrol at that same price is a syn blend). And another vote for the Dorman pan too

 

[barkingspider]

I would use whatever is cheaper. I use both in many vehicles and they both work fine

 

[Lubener]

Originally Posted By: Linctex
Originally Posted By: Lubener
One major problem contributor is small metallic particles finding their way to the solonoids. Much of that can be found on the pan bottom and once the magnet loads up, it won't attract that stuff much anymore.


Add more magnets

I have a spin-on transmission fluid filter on my F-150, and it has 6 magnets around the inlet holes. I plan to trap 99.99999% of all ferrous metals. Hopefully the filter (10 microns Baldwin) will get the rest.


Still have to drop the pan to install and clean...You should aim for 99.999999999999999999 percent.

 

[NavyVet88]

I will give a very thorough cleaning and will do a drain and fill until I have 95 to 99 percent new in it.