DEX 6 IN A OL' 86

[L05edSS]

awhile back i did this post. https://gbodyforum.com/threads/who-has-successfully-used-dex-vi-in-their-old-200-4r.87183/ this was a great post. anything i say is not a trash on anyone so don't take it that way. no matter where i looked i could not get a straight answer. i got the filter & fluid switched out NOT A FULL FLUSH! 7 qts is what i bought. my mechanic said 'pan was clean, but fluid was low and tailshaft was more sloppy with yoke out than normally used to'. the dex 6 used was not synth and was STP autozone purchased. damn that sh*t wasnt cheap....

so i took it out twice and the 200 4r shifts fine no noticeable changes better or worse. 2 things i will post if it fails but if it does can i blame dex 6? it gas 72k miles on it. and if it fails i have a spare from my last ss built in 2001 by bruce tolle NCTB (northern california turbo buicks) with 15k on it. so not too concerned and i will post if i have a failure.

sincerely,

your crash test dummy

 

[69hurstolds]

Doubt if your tail shaft sloppiness isn't a function of fluid. Unless clearances on the rear planet are opening up on you due to the fluid not doing its job.

The label on the STP stuff looks a tad misleading. Something of "For certain GM vehicles" yet it doesn't explain what that means. On the back it says something like for use where Dex II or III is called for. Well, DUH!! That's what all Dex VI is supposed to be since it's backwards compatible. True, nowhere does it say synthetic. Which is no big deal, but most of the big name Dex VI are synthetic. So...what is this STP stuff? I think it's a lot of marketing hype because if it didn't meet the Dex VI specs at minimum, GM would be all over them like a hobo on a ham sandwich. I don't think STP would be that stupid.

It may be a base Dex VI with an additional friction modifier package or something. There's something there that allows them to call it Dex VI, otherwise it's Dex/Merc.

With that said, I'd have no issues running full syn Dex VI in a 200-4R any day of the week. Better stability and less foaming, yadda yadda.

If you're worried about straying from Dex III, go with synthetic ATF from Mobil 1. If you go through Amazon, it's actually a bit cheaper than the STP non-syn stuff if you buy the 6 pack right now. $61.99 for 6. ($10.33 each) plus any sales tax to your door. Hawks Motorsports advertises it for $7.99 per quart, which is great, but once you add in the shipping and 5% handling fees for 6, you're right about the same price as Amazon's anyway.

 

[86LK]

Doubt if your tail shaft sloppiness isn't a function of fluid. Unless clearances on the rear planet are opening up on you due to the fluid not doing its job.

The label on the STP stuff looks a tad misleading. Something of "For certain GM vehicles" yet it doesn't explain what that means. On the back it says something like for use where Dex II or III is called for. Well, DUH!! That's what all Dex VI is supposed to be since it's backwards compatible. True, nowhere does it say synthetic. Which is no big deal, but most of the big name Dex VI are synthetic. So...what is this STP stuff? I think it's a lot of marketing hype because if it didn't meet the Dex VI specs at minimum, GM would be all over them like a hobo on a ham sandwich. I don't think STP would be that stupid.

It may be a base Dex VI with an additional friction modifier package or something. There's something there that allows them to call it Dex VI, otherwise it's Dex/Merc.

With that said, I'd have no issues running full syn Dex VI in a 200-4R any day of the week. Better stability and less foaming, yadda yadda.

If you're worried about straying from Dex III, go with synthetic ATF from Mobil 1. If you go through Amazon, it's actually a bit cheaper than the STP non-syn stuff if you buy the 6 pack right now. $61.99 for 6. ($10.33 each) plus any sales tax to your door. Hawks Motorsports advertises it for $7.99 per quart, which is great, but once you add in the shipping and 5% handling fees for 6, you're right about the same price as Amazon's anyway.

some interesting reading...

DEXRON - Wikipedia

en.wikipedia.org

"GM licenses the name and specifications to companies which manufacture the fluid and sell it under their own brand names. Not all Dexron fluids are licensed by GM for reselling under another brand name. To be licensed, the product must have a license number that begins with the letters B through J and include a “Dexron Approved” sticker on its container"
"The newer fluids are not always backward compatible with previous fluids..... See the details below for backward compatibility of each fluid"
"The quart containers of Dexron ULV must be shaken to stir up the additives before pouring. This fluid is not backward compatible with any previous fluids."

DEXRON - Wikipedia

en.wikipedia.org

All Dexron-III (H) licenses expired permanently at the end of 2011, and GM now supports only Dexron-VI fluids for use in their older automatic transmissions. Aftermarket fluids asserted by their manufacturers to meet Dexron-III(H) and earlier standards continue to be sold under names such as Dex/Merc. These fluids are not regulated or endorsed by GM.

GM Dexron-VI(J) licensed products have a license number on the container that begins with the letter J. Example: J-60301. This was the first GM ATF to advertise 100,000 miles (160,000 km) between changes for "Normal Driving" conditions and 50,000 miles (80,000 km) for "Severe Service". This fluid is backward compatible with Dexron-III(H) and Dexron-III(G) fluids only.

 

[69hurstolds]

GM wouldn't license the name to a product that did not at least meet the minimum specifications to wear the brand name. At least they didn't use to. Who knows now with their money grabs.

 

[86LK]

GM wouldn't license the name to a product that did not at least meet the minimum specifications to wear the brand name. At least they didn't use to. Who knows now with their money grabs.

my understanding from reading thru it sounds like GM is aprt of a working group that helped develop standards for the DEXRON fluid, which is why Ford also sells it as MERCON. don't know about the money grab for Dexron, but I do know about the money grab for DEXOS oil certification. they wanted a lot of money from the oil companies if they wanted Dexos stamped on their bottles

 

[69hurstolds]

my understanding from reading thru it sounds like GM is aprt of a working group that helped develop standards for the DEXRON fluid, which is why Ford also sells it as MERCON. don't know about the money grab for Dexron, but I do know about the money grab for DEXOS oil certification. they wanted a lot of money from the oil companies if they wanted Dexos stamped on their bottles

Yeah, Ford and GM were working together on a joint venture to bring out the 6 and 10 speed automatics, and miraculously, a new standard of fluid to boot. It's a club.

Some cars use the same parts and materials across company lines. For example, the cross shaft locking pin on GM differentials is the same part used on Fords and Chryslers. So guys working on their Fords/Chryslers can cuss the same amount about that likely broken pin when trying to remove it too, I would guess. It's just that Ford just had to give it a secret code part number like they do everything else.

GM part number 25872305 (List price is about $7.50) is equivalent to
Chrysler- 3507724 (List price over 18 bucks)
Ford - D8BZ4241B and D8BZ4241C (List price from Ford is $7.65)

And the Dexos money grab seems to be just that. Kinda funny, at first, Mobil 1 wasn't "Dexos approved", and then, all of a sudden, it was. Still trying to figure out who actually makes the oil for those GM bottles.

Here's an excerpt from an email from a member on Bob is the Oil Guy:

I had emailed Mobil Oil as to why the Mobil Full Synthetic was not Dexos 1 approved: May 7th 2020 Mobil response: I'm not clear, yet, on why this does not carry a Dexos1 approval, but it's on our agenda for a conference call on Monday. You probably won't be the only customer with this question, and I want to be sure we get the right answer. As long as it does not carry a GM license, however, I can not recommend it in any 2011 or newer GM vehicle. May 11th 2020 Mobil response: Happy Monday! We just wrapped up our call and I've got some good news. Mobil Full Synthetic in 0W-20 and 5W-30 will be receiving GM Dexos1 approvals. With the current COVID-19 situation, approvals are slow coming as the testing labs are not considered "essential." So it appears Dexos 1 approval is just delayed due to the backlog at testing/certification labs.

I still use Mobil 1 in nearly everything I have, but I do use the GM Dexos in the truck and CT5 for warranty concerns only and have the dealer change the oil (I use their $79.99 6-quart and 89.99 oil change 8-quart coupons and it costs me just a few bucks more than doing it myself and they rotate the tires, top the fluids and do the "inspection" whatever that is, too). My cost would be about $60 for 8-quarts of the "Dexos" Mobil 1 oil, I'd buy a better oil filter for around $20 for the Mobil 1, and that's 80 bucks right there. About $70 if I did a GM filter. And then not even hassle with getting rid of the old oil and all that. GM is too quick to jump on anything to void your warranty nowadays. After the warranties are out, though, I'll probably go to Mobil 1 for everything again. Never ever had any oil-related issues with Mobil 1 in anything I've used it in.

 

[L05edSS]

Doubt if your tail shaft sloppiness isn't a function of fluid. Unless clearances on the rear planet are opening up on you due to the fluid not doing its job.

The label on the STP stuff looks a tad misleading. Something of "For certain GM vehicles" yet it doesn't explain what that means. On the back it says something like for use where Dex II or III is called for. Well, DUH!! That's what all Dex VI is supposed to be since it's backwards compatible. True, nowhere does it say synthetic. Which is no big deal, but most of the big name Dex VI are synthetic. So...what is this STP stuff? I think it's a lot of marketing hype because if it didn't meet the Dex VI specs at minimum, GM would be all over them like a hobo on a ham sandwich. I don't think STP would be that stupid.

It may be a base Dex VI with an additional friction modifier package or something. There's something there that allows them to call it Dex VI, otherwise it's Dex/Merc.

With that said, I'd have no issues running full syn Dex VI in a 200-4R any day of the week. Better stability and less foaming, yadda yadda.

If you're worried about straying from Dex III, go with synthetic ATF from Mobil 1. If you go through Amazon, it's actually a bit cheaper than the STP non-syn stuff if you buy the 6 pack right now. $61.99 for 6. ($10.33 each) plus any sales tax to your door. Hawks Motorsports advertises it for $7.99 per quart, which is great, but once you add in the shipping and 5% handling fees for 6, you're right about the same price as Amazon's anyway.

yeah i got all kinds of answers like can't use dex 6 on pre 2003 trans or something. its been a longtime since done a filter change and the trans is the unrebuilt 200 4r and never considered the fluid updates but have heard changing fluid destroys em sometimes. 1 way or another i'm gonna have to go with the newer stuff eventually so better start getting used to it now whatever the consequence if any.. hope it helps someone else down the rd.

 

[64nailhead]

I’ve been running Dex 6 in a 200 for a little bit and it’s been in my ‘92 80E for a full season of abuse - no issues what so ever. You’ll be fine - other than the price haha.

All ATF has skyrocketed, it’s not just the GM stuff. Do a price check on synthetic Allison fluid if you want some real sticker shock.