Specialty Formulation tranny and diff fluid

[Whimsey]

I finally had the chance to install the SF SynchroGlide tranny fluid and HDS-5 75W-90 rear diff fluid in my 2002 F-150 with the Mazda MOD5 tranny. The manual tranny is spec'd for Mercon ATF. Not a happy combination even with the Schaeffer's #204S. Though the Schaeffer's #204S Mercon was 100% better than the factory Mercon

. It still sounded and felt "clunky" with the ATF fluid. I went with SF's SynchroGlide tranny fluid and whoa, what a positive improvement in shifting quality in the only 50 or so miles I've driven so far since the fluid change. It's a slightly more viscous fluid than ATF and is totally synthetic with EP and AW additives that ATF doesn't have.

I dumped my rear diff Ford 75W-140 fluid, There is about 20,000 miles on it. It was an opaque grey fluid that came out. There is no magnet in the diff cover. Also this diff does NOT have limited slip. I refilled with SF's synthetic 75W-90 gear oil. It could be my imagination but I didn't have to down shift out of 5th to 4th to get up the same hills where I normally have to downshift. Could the 75W-90 SF gear fluid vs 75W-140 Ford gear fluid make a difference

? As I said previously I don't tow but 2,000 lbs one in a blue moon and don't offroad, unless muddy construction sites count as off road

.

Whimsey

 

[DJ]

I will be going to the AutoGlide in one and maybe both of my 4L60E equipped cars. I say maybe both because I have to get a UOA done on the special brew the tranny builder has me running in one before I decide to switch away from it. Terry will be helping me there. I look forward to trying these products as we know the brewmaster for them is a heck of a guy.

I am debating ordering the gear lube too, I mean as long as I have an order comming might as well get everything I could need right.

 

[JoggingGuy]

quote:

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Originally posted by Whimsey:
I dumped my rear diff Ford 75W-140 fluid, There is about 20,000 miles on it. It was an opaque grey fluid that came out. There is no magnet in the diff cover. Also this diff does NOT have limited slip. I refilled with SF's synthetic 75W-90 gear oil.

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Hey Whimsey, what did you use in that differential? HDS-5?

 

[Whimsey]

quote:

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Originally posted by JoggingGuy:

quote:

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Originally posted by Whimsey:
I dumped my rear diff Ford 75W-140 fluid, There is about 20,000 miles on it. It was an opaque grey fluid that came out. There is no magnet in the diff cover. Also this diff does NOT have limited slip. I refilled with SF's synthetic 75W-90 gear oil.

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Hey Whimsey, what did you use in that differential? HDS-5?

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Yep, that's what I used. So far it's just as quiet as it was with the Ford 75W-140 diff fluid. Though if I did any heavy duty towing I would have went with the SF HDS-5 75W-140. But I don't tow so I figure if I can squeeze an extra 1/2 mpg with the 75W-90 vs the 75W-140 I'll be better off in the long run. Especially with the price of gasoline now and the anticipated future. Plus the protection most likely is at least the same if not better for me.

Whimsey