Feels different after differential fluid service

[scottiep]

Hi all.

I hit 36k miles in my '19 GT and I had my local mechanic drain and replace the differential gear fluid. And I've noticed that since then, as I'm pulling out of my garage (going forward) and cutting sharply left, that I'm feeling (through the break pedal ever so slightly) sort of a subtle grinding/scrubbing.

I had him look at the car and he made sure brakes and wheels were good--not scrubbing anything. But I continue to feel this--mostly when turning the wheels sharp in one direction or the other. So, I wondered if it was something about the gear oil, but he assured me (and the local Kia dealer confirmed) that this LSD doesn't need any friction modifier. He believes that the hypoid fluid he used should be compatible and not need any additive (he used Motorcraft SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant).

Does anyone have any experience with this? Should I crawl under there, drain it and use some other oil? I do feel like I am obsessing over it a bit, but something just feels different. Could it be that everything is fine and that the change in the oil just makes it feels different?

thx!

 

[bfglitch]

Don't know if I would trust that. It's formulated specifically for Ford and says nothing about meeting API GL-5 requirements which is what is recommended by the 2019 LSD.

 

[scottiep]

Thanks for the reply. Yeah, that was what I was wondering.

 

[Volfy]

This thread has all the info you need. LSD Service Bulletin - Oil Update

3 ways to do this:

1. Get the Kia-branded LSD oil, as specified in the TSB
2. Get a know good LSD oil that already have enough FM added. Amsoil, Ravenol, and Redline, I believe, are in this category.
3. Get a good synthetic 75w85 or 75w90 GL5, and add FM.

 

[scottiep]

This thread has all the info you need. LSD Service Bulletin - Oil Update

3 ways to do this:

1. Get the Kia-branded LSD oil, as specified in the TSB
2. Get a know good LSD oil that already have enough FM added. Amsoil, Ravenol, and Redline, I believe, are in this category.
3. Get a good synthetic 75w85 or 75w90 GL5, and add FM.

Awesome—thanks!

Yeah, I was thinking of using Amsoil Severe Gear 75w90. Sounds like it’s GL-5.

 

[Ah GetFd]

Hi all.

I hit 36k miles in my '19 GT and I had my local mechanic drain and replace the differential gear fluid. And I've noticed that since then, as I'm pulling out of my garage (going forward) and cutting sharply left, that I'm feeling (through the break pedal ever so slightly) sort of a subtle grinding/scrubbing.

I had him look at the car and he made sure brakes and wheels were good--not scrubbing anything. But I continue to feel this--mostly when turning the wheels sharp in one direction or the other. So, I wondered if it was something about the gear oil, but he assured me (and the local Kia dealer confirmed) that this LSD doesn't need any friction modifier. He believes that the hypoid fluid he used should be compatible and not need any additive (he used Motorcraft SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant).

Does anyone have any experience with this? Should I crawl under there, drain it and use some other oil? I do feel like I am obsessing over it a bit, but something just feels different. Could it be that everything is fine and that the change in the oil just makes it feels different?

thx!

Over servicing is what dealers invented.

There is absolutely no need to change diff fluid if there has not been any leaks or repairs. Leave it alone.

Now that you F....d with it you have a problem.

You can probably fix it with a diff additive. AC Delco has one or put back the original fluid at a KIA DEALERSHIP.

Waiting for the haters who are gonna hate..............especially that DH who thinks you should service cars three years before it's due............

 

[CeramicGT001]

Awesome—thanks!

Yeah, I was thinking of using Amsoil Severe Gear 75w90. Sounds like it’s GL-5.

I just did the rear differential myself last weekend with the Amsoil fluid you listed, car drove perfect all week. 2019 with about 58k miles, the old fluid was diiirty. Going to have the dealer do the front diff soon, I’ll provide them the Amsoil fluid for that too.

 

[Clubber]

Over servicing is what dealers invented.

There is absolutely no need to change diff fluid if there has not been any leaks or repairs. Leave it alone.

Now that you F....d with it you have a problem.

You can probably fix it with a diff additive. AC Delco has one or put back the original fluid at a KIA DEALERSHIP.

Waiting for the haters who are gonna hate..............especially that DH who thinks you should service cars three years before it's due............

You are correct !! I'm at 140,000 miles on my 19 GT AWD and it's running fine. Hopefully I'll make it to 200, then I may drain and refill front and rear, as I plan to keep this car until I kick the can.

 

[Ah GetFd]

Gees that post was a while ago.

I kept GM cars for 14 years 20 years and 22 years concurrently and never changed the diff oil or transmission fluid. They ran like new.