I hope Royal Purple is worth it...

[01rangerxl]

I sort of did an impulse buy that I hope is worth it. I decided to get Royal Purple 75W90 for my truck's differential. It's complete overkill, at at $18.99 a quart, way more than I planned on paying.

I decided nothing but full synthetic was going in there this time. I used Valvoline DuraBlend 75W90 before this, and it turned very dark. Much darker than the OEM fluid got with 20K fewer miles on it. Kind of disappointing.

I'm waiting on the RTV to set now. Despite the fact that some other members have had problems with Permatex Ultra Black leaking after a period of time, it worked great last time for me, so I used it again. It better work again because that RP is way too expensive to leak.

 

[outrun]

I think what is overkill is the 18.99$/qt you paid. I still get Redline and Mobil 1 gear oils for less than 11.99/qt.

Can you return it and find a cheaper vendor? You differential does not have a gasket?

 

[Colt45ws]

The 8.8 does not, no. You can get cork gaskets from some auto parts stores. Worse, IMO, than RTV.

 

[JohnBrowning]

Wow RP wouldnot be choice at that price. I am sure it will work just fine your diff. but I would avoid their transmission fluids for manuals and such they suck!

 

[01rangerxl]

Pep Boys is the only reasonably close store that carries RP, they know it, and that's their price. I'm not going to order gear oil online or anything if I can avoid it. I'll probably leave it in for 60K or so.

My truck came from the factory with an RTV gasket, so that's what I use. Cut gaskets are available, but I just use the RTV. I have the 7.5 axle, so unfortunately those are my options. There are a couple reusable rubber gaskets available for 8.8s, but none for 7.5s.

 

[tomcat27]

part of the pricing problem is the price that RP gives stores. they dont leave them enuf margin to charge normal price for it. same with amsoil.

 

[Nayov]

There are better choices than RP. I posted a link to a comparison study and it consistently ranked at the bottom (their diff oil). I searched for the link but it doesn't show up. Also, that isn't a good price. Even Amsoil is cheaper. I paid $15.99 over-the-counter.

 

[chambers]

Originally Posted By: JohnBrowning
but I would avoid their transmission fluids for manuals and such they suck!

Care to elaborate and maybe link to evidence of that?

Originally Posted By: Nayov
There are better choices than RP. I posted a link to a comparison study and it consistently ranked at the bottom (their diff oil).

Which comparison, is that the amsoil white paper that is always thrown around? If it's something different please post the link here as I would like to look at it.

RP gear oil is usually far too expensive, but to be fair I think Mobil 1 was about the same for 75w-140 which is what I needed.

 

[Nayov]

^ Yeah the darn search engine can't find it. Not sure if it was the
amsoil sponsored one. Probably was as they are famous for using that tactic.

 

[Nayov]

www.amsoil.com/lit/g2457.pdf That's the one.

 

[wander2039]

Guess you didn't see my post a while back.

This is what 75w90 looked coming out of my 7.5 at 30k. I put dino back in. Not worth spending the extra if it's going to look and thin that bad.

 

[01rangerxl]

Hmmm...we'll see how it does I guess. Hopefully I'm not dumping this after 30K.

If the RP doesn't work out, I'm just going with Motorcraft 80W90 again. The factory fill looked really good even with 55K on it.

 

[aquariuscsm]

The Toyota dealer here sells it for $6.99 a quart.

 

[aquariuscsm]

Use Amsoil AGL 80W90.

 

[aquariuscsm]

Originally Posted By: Eric Smith
Guess you didn't see my post a while back.

This is what 75w90 looked coming out of my 7.5 at 30k. I put dino back in. Not worth spending the extra if it's going to look and thin that bad.


What kind`ve oil was that in the pic?

 

[AzFireGuy79]

Just because it was dark hardly means anything. Did you have a used oil analysis done on the valvoline? RP shears like a mad dog. Not very good gear oil. I run Redline, Amsoil and M1 depending on which one is available at the time, though I prefer RL. $18+per quart!

 

[OVERKILL]

I'd try to find some Delvac gear oil........

 

[wander2039]

That's was RP's 75w90.. and I know being dark isn't a good indicator. You can tell when a gear oil thins though which it did. I highly doubt it was protecting anything being that thin.

 

[Jason2007]

Ive had RP Syncromax in my 07 Mustang GT's manual transmission for almost 18 months and about 13k. Transmission has never shifted better. I also have RP 75w140 in the rear put in at the same time. Works great. Also, M1 75w140 is now about the same price as RP 75w140.

 

[jmac]

I'm on my second fill of RP 75w-140. Reason for the longest time I could get it at substantial savings over M1 at normal OTC prices here and at the first drain the oil was dark but still clear, gear box and gears were clean and great looking. If your first drain is at 30k anything that was in there usually comes out nasty looking and thin. The MC GL that came out of my rear end the first drain looked really nasty.
RP made its name on gear lubes, in field customers replaced the best gear lube by Mobil in many oil field gearboxes to double or more the change intervals and lower the breakdown or overhaul rate.
I doubt if there is a price increase to match those prices it is wholly due to corporate increases. In many cases I have seen price increases on all kinds of things with the retailer taking the majority of the difference from the increase.