Differential Fluid - Issue or No?

[TWG1572]

I have a Nissan Frontier with approx 30K miles. I decided to change the differential fluid at 30K, since I did it myself I figured the $25 on new fluids was money well spent. I put Mobil 1 75w90 in the rear, and Valvoline semi-syn 80w90 in the front. (The service manual specs the two different weights, and synthetic for the rear.) Life was good..

Since my bumper to bumper warranty is about up, I took the truck in the next day to get some issues fixed. Plus, I had them do a couple other routine maintenance things since I didn't have time.

Long story short, the tech *assumed* that my truck was in for the full 30K "Premium" maintenance package - part of which was replacing the diff fluid. He dumped both with about 5 miles on them. Per the invoice I got back, both were refilled with 80w90.

I called and talked with the service manager - he credited me the labor/parts and claims that their fluid was syn. Evidently, their standard fill is 80w90 in both diffs.

They claim all is well, and consider the issue made right. But, right now I'm cranky for several reasons.

1) They only credited me about $43 for the diff fills and labor. That seems really low, but I can't see what they initially charged me because it's billed as a package of 30K services. For reference, I think I paid $25 for the gear oil when I bought it from AutoZone.

2) $5 per quart for syn at the dealership seems too cheap. Plus, I don't think there is a 80w90 syn available except for Amsoil. Which leads me to wonder if it really was synthetic.

3) There is 80w90 in both axles. Manual says 75w90 in the rear. Probably not a big deal in the entire scheme of things because it's probably not going to cause an issue, but I had it right and they should make it right again.

*end rant* Am I just being cranky? I'm tempted to go back and ask that they put my origional fluids back in (at their cost), but I need advice and information from people who know this sort of thing better than I.

Needless to say, that is the last trip there for anything other than warranty work.

 

[MolaKule]

Well, I would have simply told the shop I had just replaced the diffy fluids and not to touch the diffys.

A lack of communications maybe?

 

[snakerupa]

Just to CYOA, I would change back to manuf. recommendations. Preferably at the 'stealers' expense. If they won't do it, get something in writing on company letterhead for warranty issues. Being a Nissan owner (05 Pathy, bought new, now w/ 100k), I know first hand they will try to deny any warranty repairs for the slightest reason.

 

[ryan2022]

hmm, I dont trust many dealerships. There are just too many ways for them to slip one by you.

I'd be iffy with that as well. I wonder if theres a way to tell if the fluid is synthetic or not by a UOA?

Its a tough call.

 

[d00df00d]

You definitely have grounds to go back and make them fix their mistake. If this issue bothers you on principle, go ahead and make them fix it.

Otherwise, the question is whether it's worth the better part of a day of your time. Keep in mind that you have lost a little bit of leverage since you drove off the lot with their fluids.

I think you're right that the 80w-90 is probably not fully synthetic. I suspect it's a syn blend, and the service manager was calling it synthetic because he's used to people not knowing the difference. Then again, I also suspect you are right that your rear diff will probably be fine.

Here's what I would do: First, contact Nissan Corporate and ask them what the correct fluid is. If they confirm what's in the owner's manual, ask for a letter, take it to the service manager at the dealership, and wave it in his face until he gives you a refund or agrees to put the correct fluids in. If they say you'll be fine with the 80w-90 semi-syn the dealership gave you, ask for a letter to that effect, file it away, and sleep easy.

 

[saberz]

I paid roughly $10 a bottle for Mobil 1 Synthetic 75-90. The Pennzoil dino diff fluid was roughly 4-5 bucks. They do not make a synthetic 80w-90 that I know of. I used the 75w-90 in both my front and rear diff's on my Xterra(same vehicle if you have a 99-04 Frontier).

 

[Bluestream]

I wouldnt get too bent about it. The fact that is was changed at all is the bigger issue. The fluid they used is fine..

 

[DieselTech]

80-90 is usually dino 75-90 is syn

 

[Johnny]

What part of WI are you in? What dealership was it? Ask them what brand of gear oil they use.

 

[MaximaGuy]

Originally Posted By: d00df00d
You definitely have grounds to go back and make them fix their mistake


What mistake, the dealership followed the book in changing the gear fluids as per the warranty. As Molakule said,the poster should have told them not to change the gear fluids, I second that argument.

 

[TWG1572]

Originally Posted By: MaximaGuy
Originally Posted By: d00df00d
You definitely have grounds to go back and make them fix their mistake


What mistake, the dealership followed the book in changing the gear fluids as per the warranty. As Molakule said,the poster should have told them not to change the gear fluids, I second that argument.


I wasn't clear enough when I wrote my initial posting - not only did I tell them not to change my diff fluid, they also gave me a sheet of their typical 30K maintenance where I crossed off all the maintenance items that I did not want done. So in reality, I told them twice. Thankfully they didn't re-change my oil, air filter, etc...

 

[Tommyboy]

If it were me, I'd treat it like dino fluid and change it sooner than you probobly were going to w/ syn. And then,in the future, remember to be as specific as possible when talking to shops, dealerships or otherwise. I don't think it's worth your time and trouble to go back in and fight over this one. You've probobly got bigger things to get aggravated over!

 

[TWG1572]

Originally Posted By: Johnny
What part of WI are you in? What dealership was it? Ask them what brand of gear oil they use.


I'm in Madison. I'm going to leave the dealer's name out right now, just because I don't want to start flaming them by name just yet. I'll PM it - I know they use PYB for bulk.

 

[Johnny]

I use to cover the Madison area and worked closely with the Pennzoil distributor down there. Try and find out what brand gear oil they used and maybe I can help put your mind at ease.

 

[Boomer]

Nissan really wants syn fluid in their rear diffs as they have had some heat failure issues (mostkly the upgrade axle, not the 200 type) and that means 75W-90. I'd change it back and find another place to get service. I run Mobil 1 75W-90 in the rear and Valvoline 80W-90 Semi-Syn in the front diff of my 2007 Frontier.