Exactly , my new to me 98 Cummins Ram must have +4 in it because the lockup shift is real lazy, I'll be refilling it with the dex/merc next time around ... I have a case of dex3 I bought probably 20 years ago , but I'm saving that for something special ...

You are feeling something on lockup but it’s not a slow lockup engagement, unless you are setting a lockup code.

The controller starts a “clock” once lockup is commanded. If it takes too long, it sets the code. Never seen a code set due to fluid type, always an internal trans issue.

Lazy is just the generic term I'm using, it's Soft. My other truck has a low stall convertor , higher pressures and uses Dex3 , the lockup is firm .

EDIT ... I looked thru an old Sonnax catalog I have and it has a replacement switch valve to deal with the SOFT TCC apply ... their words ... apply of the lock up clutch. https://www.sonnax.com/parts/1839-4-spool-switch-valve

sorry for going off topic ...

Not long ago I could get it at Walmart, their brand was $4.77 for what seems like forever.
But the last 2 times I've had to buy ATF, whether+4 or dexron, prices have gone stupid. Last time I needed some +4 I had to go to like 3 different places to get enough to do a pan drop/fluid and filter job, and $10/quart was at the low end of what I had to pay.
Used to be I could fill a newly built trans and converter for $50. Now a days I can't do a pan drop for that.

I've got receipts from the 70's in which I bought everything to rebuild kit a 727 with good clutches, bands etc. and a TF-2 shift kit for under 40.00

My trans has a manual valve body in it. Would the extra friction modifiers really matter, since I am manually shifting it? Is there a concern with clutches slipping because of the extra modifiers?

I know I have some atf4 7176 and I believe soem old stuff also.Last used when my youngest had the 04 Ram Now we all have new vehicles except for me having my 65 4 speed.Might just sell it off at the crazy prices

i'm still using generic all purpose atf that came from a 55 gallon drum in my wife's car, a 94 concorde, and my "bus", a 99 caravan.
i still have four or five gallons of that, plus what is scattered around in the shop in one gallon jugs that aren't empty, maybe a quart or two in each jug.
i have no idea what this stuff really is, but it works fine in those applications. however, i don't drag race these things either.......
i have quite a few quarts of type F on the shelf of different brands, but maybe i should think about stocking up. [just what i need.......more "stuff" to store...... ]

Fleet Farm

Type F

$4.75 a quart

For those that use Dex Merc in newer stuff lowes has it in 2.5 gal jugs for $25. That's $2.50 / qt. Isn't that like decades ago?
https://www.lowes.com/pd/MAG-1-Mag-1-Auto-Trans-Fluid-Dex-Mer-2-5-Gal/5001933159

The manual shift alone will not make a difference in how fast the clutch packs grab or how much they slip. The friction modifiers in the fluid WILL affect how fast the clutches grab and how much they slip.

If you are racing then fast clutch grabs are a good thing so slippery friction modifiers are a bad thing. That is why I use Type F and not ATF+4.

BUT

There are several things inside the transmission that can affect how fast and hard the clutches grab so some transmission builders will specify certain fluids for specific reasons including softening the shift among other things.

First go by the transmission builder/manufacturer specs. If they don't have any, then I use Type F / Dexron.

The transmission still applies clutches and bands the same way whether it shifts manually or automatically.

If you're not experiencing slipping now then as long as you haven't done a huge increase in torque you'll probably be fine, but why risk it? I don't think any of the big power diesel trans builders are using, or recommending +4 , I know my mentor was totally against it back in 2001 when I was working for him. My 2000 Cummins Ram only had + fluid in it for the first 30k miles , after that I never used it .

This is even cheaper , not in stock at my store but buy 4 jugs and shipping is FREE ...

https://www.lowes.com/pd/MAG-1-Mag-1-Auto-Trans-Fluid-Dex-Mer-Gal/5001933105

On a race trans. things are done to get the elements to apply more aggressively, i.e. eliminate the function of accumulators which act as a cushion for the shift, crank up the pressure, use more aggressive friction materials, etc.. Applying frictions, starting and stopping elements quickly behind big power at WOT is much different than a smooth, unfelt shift at light throttle on the street.

Also the use of fluids that are not as slippery as modern fluids which are designed to make the application of lock up converters and frictions elements nice and smooth to satisfy the public.

I tried some Amsoil Synthetic street fluid once. The high gear plates came out black streaked from heat, obvious slipping on application. Never had it before, never had it after I went back to Type F. Good fluid. Not the right application. They do a synthetic racing Type F modeled after fluids used in transmissions in heavy equipment that need to shift while pulling heavy loads.

On topic, ATF shelves are empty at local auto parts, and it has been expensive for awhile. What does show up is gone in less than a day. Heater and fuel hose is also scarce. Next month it will be something else. This is the new normal.

The reported cause is a shortage of some additives.

And the Mag 1 brand of oils is cheap stuff kept for oil changes at shops who want the cheapest crap possible. Not even sold to the public. I have a little inside knowledge of what's going on in the local Advance stores.

How is it cheaper? The 2.5 gal jug I linked is $10 /gallon. The 1 gal jug you linked is $12.

Sorry my bad ... I'm blaming it on new math ...

I won't be wasting time getting any of that then. Thanks

I ran into this issue with the high price and limited availability of a wide variety of transmission fluids in this area a few years ago. Luckily, when Pep Boys decided to stop selling auto parts and transition to just servicing cars, I bought several cases of old school Type F and Dextron transmission fluids for dirt cheap, since they wanted to liquidate inventory. They were getting rid of cases of their house brands of transmission fluid for a little more than a dollar a quart.

Thanks for the info, everyone. I'm going to re-evaluate what im using.

I will say that I know any number of class racers who use Super Tech (Walmart) Type F in high dollar trannies, so there's that.