Different brand of fluids?


I am wanting to know if it’s harmful to a vehicle if I add a brand of fluid (eg. transmission, engine, power steering etc) that’s a different brand from the one that’s already in the vehicle? Imagine in this scenario that other than brand, the fluids have the same specs that’s required for the car.

Thx in advance

Most cars no, but if you have a Honda or an Acura, you want to use the Honda power steering fluid, brake fluid, and coolant (edit: and transmission fluid). Its about the same cost from the dealer.

Motor oil isn’t a problem. Brake fluid isn’t a problem. Some auto transmissions are very sensitive to fluids so I’d not mix auto tranny fluids. Coolant can be topped off with another brand, but if you have a significant leak with need for frequent coolant top offs, you need to figure out the problem.

Honda CRV are very sensitive to differential and transfer case fluids. If you are talking about a Honda, then stick to Honda brand fluids to be safe for all the fluids, brake fluid is the only exception in my opinion on a Honda.

It has nothing at all to do with brand - no matter what. Its always about the specifications. There aren’t even as many brands out there as it looks like since these days the same companies put the same stuff out under multiple labels according to different sales strategies and contracts with end sellers. Sometimes its best to buy a fluid with a specific label on it (e.g. “Honda”) because it might be either the only way to get the correct spec OR the only way to be sure that you’re getting the correct spec.

No, it’s not harmful. You can use any brand fluid or oil in your car as long as what’s on the label says the fluid meets the requirements of your car. For example if your Chrysler product uses ATF+4 transmission fluid you can use any brand that meets that specification.

But beware of interpreting that label. One company makes a transmission fluid that says it is “approved for use where Dexron, Mercon, MerconV is required.” Then it says “additionally recommended for use where Toyota T-IV, Mitsubishi sp-II, Honda Z-1 is required.” That means that the company making the fluid says it’s good enough but that Toyota, Honda, and Mits haven’t approved it. “Approved” is the key word.

I just stick with the national name brands and I’ve never had a problem. I don’t own a Honda so I guess I can continue to mix to my hearts content.

If you’re talking mixing at will (as opposed to changing out) then I’m going to be conservative is some cases
Oil - same grade, no problem
Brake fluid - as far as I know all use DOT 4 compatible fluids, but check
Transmission fluid - here I would make ABSOLUTELY SURE I’m using fully compatible fluid, and I’d just spend the extra to get a bottle of the factory fluid for topping up
Coolant - used to be simple, not so now. I pulled the fluid specs for Ford, there are 4 different coolants they’ve used since 2000. So for topping up I’d find out what’s in there, then use exactly that. For flush and fill, you have more choices.

I kinda agree with the above. Any brand oil that meets specs for the engine when doing an oil change, but use the same brand when topping off between oil changes. Brake fluid, use what ever is specified for top off, but if you flush the complete system, use any approved brake fluid and then use that only for top off.

Same for coolant. Almost any coolant can be used in any vehicle, some some are not compatible with each other, so if you do a complete drain, radiator and block, you can use almost any coolant. Most vehicles today with all aluminum engines cannot tolerate the old coolants that contains certain phosphates and borates, but all can use the universal long life coolants as long as you do the complete drain and refill.

Transmissions are a different story. You may be able to use certain national brands that meet the specifications of the factory ATF, but they usually cost just as much as the stuff from the dealer. I would go with the dealer supplied ATF unless for some reason you cannot get to a dealer where you live.

Always use Honda transmission fluid in a Honda and always use Toyota Long Life engine coolant, if that’s what it came with.

Some cars, like many European models, have a very tight spec for motor oil. Make sure the oil you use meets that spec!

There isn’t a car manufacturer that makes their own fluid. They are all made for them by some other company.

There are several companies that make Honda transmission fluid…along with Honda power-steering wheel fluid. Same with the Toyota WS fluid. However many times it’s just as cheap to buy the stuff from the dealer. Honda power-steering wheel fluid was about half the price of the STP Honda power-steering wheel fluid I could buy at ADAP. Toyota’s WS transmission fluid is the same price as the aftermarket stuff from Valvoline and Amsoil. But check around. Just make sure it’s 100% compatible. Don’t settle for a substitute.

I’ll take a different stance on brake fluid. You need to check the specs for the recommended fluid and replace it with similar fluid. DOT fluids specify a minimum boiling point, and it can be higher. I use the highest boiling point DOT4 brake fluid I can find as a replacement for the Honda fluid, and it works fine.

With ALL fluids it’s critical to check your owner’s manual and use the correct fluid, and it’s critical to ensure that it has API and ASE certification badges on the label.

Oil brands are readily interchangeable as long as the specs are right.
Some trannys are very particular, so I recommend always getting the exact fluid from the dealer.
There have also been problems with mixing different types of coolant, so I also recommend getting the dealer coolant. It’s better to be safe than sorry.

The damage that can be done by the wrong fluid can be very, very expensive, and very demoralizing. If in doubt, always use the manufacturer’s fluids. Peace of mind has value.

Check what the car’s owner’s manual says!

I agree with all the general sentiments. It pretty much depends upon the fluid and specs. You can get away with a lot with motor oil which for the most part, have designed compatibility. Most importantly, engine oil is changed more often then any other fluid ( except windshield washer) so cross contamination is less of an issue. Differential fluids are pretty stable as long as specs are the same. But, I would have a NO problem in adding slighly different spec fluids in an emergency to brakes, transmission, power steering and coolant, but I would be sure to make the correction ASAP when I got the opportunity. Besides, just add water to coolant till you get home in an emergency. Most sellers can get you pretty close. GM, Ford and Toyota are so common place, there is little need to use the wrong fluid and Walmarts are “everywhere”. But if doing your own maintenance in general, DO NOT BE A CHEAP SKATE. It can come back and bite you in the tosh at the worst possible time. Getting the right fluids is better for your car, and the economy, specially yours later.