SR20DET Manual Trans fluid change... why??

[RJs95s14]

hey i tried to search for this but all i found was how-to's what i am looking for is why..? Why must u change your trans fluid in a manual trans sr20 engine? i have never hurd of such in even vehicles running well over 500 hp. is it something to do with the sr20 engine? i just bought mine and was reading on here and just have never hurd of switing manual trans fluid on a regular basis.. how often do u need to change it and once again why..?

[I ask good questions]

Using redline mt-90 or any other equivalent synthetic fluid just makes the transmission shift gears smoother and helps prolong the life of the synchro's. I think they recommend to change every 20k miles or so. I loved the difference it made in my transmission!

[ILikeMy240sx]

This is a joke right? haha I lol'd.

[96EclipseGST]

Redline is sweet, but i like Lucas I use redline for my diff for the shock protection value... Redline is like syrup =P

[itsnever2fast]

Gear lube actually acts as a cushion between metal surfaces in your transmission, so they dont actually touch. The oil molecules roll around like little tiny bearings. you have to change it b/c it sheers down, the gears rip up the oil on a molecular level these little "bearings" get crushed and ripped apart. When the molecules break down the oil thins out and doesn't have the same film strength, the metal actually touches metal and the gears wear down and contaminate the oil with metal particles. When you dont change it it wears everything out, ALL conventional gear lube is SUPPOSED to be changed in 30k mile intervals, at least. Also dont forget that most SR trannies are between 15-10 years old so you do need to be somewhat carefull with them. OIL IS CHEAPER THAN A TRANS play it safe. I personaly use MOBIL conventional lubes in all my driveline and change them all out very very often, engine oil every 2.5k trans every 10k rear diff every 10k

[RJs95s14]

ok so why do high powered mustangs and such not have to change the trans fluid but every 120K but u guys change every 10.. thats a very big difference. i just didnt know if it were something to do with the sr20 engine or what..

[96EclipseGST]

Our SR trannies are weak. =P

[xero1]

ok so why do high powered mustangs and such not have to change the trans fluid but every 120K but u guys change every 10.. thats a very big difference. i just didnt know if it were something to do with the sr20 engine or what..

this is because Ford wants to sell you a new transmission. +1 for MT-90 Redline.

[itsnever2fast]

i think you are confusing peoples lack of maintainance with proper service interval.... i worked at a speed shop specializing in mustangs you should change the gear lube on anything modified at least every 30k. remember we are squeezing 250-400 horse through a transmission that is way smaller than a tremec and spins faster... AND we beat the sh*t out of our cars. just because trannies can hold togather doesn't mean its not damaged. we are avoiding damage. why ask?

[qwikxr]

ok so why do high powered mustangs and such not have to change the trans fluid but every 120K but u guys change every 10.. thats a very big difference. i just didnt know if it were something to do with the sr20 engine or what..

waiting 120k for ANY car's trans fluid change is just plain idiotic.. and no high-powered mustang will stay together for 120k, anyway.. Been there, done that. Hell, I dont know of a 'high-powered' drivetrain that will last 120k w/o proper maintenance, etc..

Yes, this is a very long post. Yes, this is basically copy/pasted from a website. No, you obviously didn't do any homework. This took me like 5-10 minutes to find this info..

from Automedia.com

Service Intervals Painless preventative maintenance Phil Coconis / autoMedia.com

You've probably heard all the excuses: "If it ain't broke, don't fix it!" "Don't they check all that stuff at the quick-lube when I get my oil changed?" "I know it's time to change my oil when the red oil light comes on!"

There are still more reasons for not doing simple maintenance, such as the using synthetic oil, or planning to trade in the vehicle in the near future, and any other excuses for not observing required service intervals. You might subscribe to some of the same rationale yourself because maybe you, or someone you know, seemed to do all right by such thinking.

Wear Means Tear

The reality is, however, that no matter how many excuses humans employ, automobiles wear out with use. The good news is that they take much longer to wear out when properly maintained. It's true that some particular models may stand up to a lack of maintenance better than others. Even so, when routine preventive maintenance is performed, these more durable vehicles will last longer and experience fewer costly breakdowns. For instance, let's start with the engine oil change, since that's the most basic part of routine maintenance.

Change is Good

It is true that many manufacturers say that it's all right to go up to 7,500 miles between oil changes, but that's recommended only under ideal conditions. They also describe "severe conditions" in which the oil has to be changed more frequently. Many people might be surprised to learn that the conditions they drive under would qualify as "severe." These include frequent stop-and-go driving (includes rush hour on most freeway/expressway routes), driving in high ambient temperatures, driving frequently over hilly terrain, driving in dusty conditions, or frequent high speed or loading conditions. Under such conditions, the oil change interval is lowered to around three months/3,000 miles, more than twice as often.

Using the red "oil pressure warning" light (not to be confused with the oil change interval light) as a signal to change the oil is a bad idea. It's true that, given an engine oil capacity of four quarts, and an oil consumption (burning) rate of one quart per 1000 miles, you might be able to make it from change to change without adding oil. This sounds appealing, since it appears to save money—on oil, anyway. The drawbacks to this approach can be extremely costly, however. For one thing, as oil burns off and there's less in the oil pan, oil temperatures go up. This will cause a more rapid burning off process, which will affect your consumption calculations. It will also promote sludge and varnish deposits, as the heat breaks down the additives designed to deal with those bogeys. There will also be less oil to suspend and neutralize typical contaminants created by the combustion process. These, in turn, start attacking the metal in the engine. On top of that, when the oil level drops low enough—usually to two quarts or less—you run the risk of the engine's oil pump ingesting air. This can happen during heavier g-loading, such as during hard cornering, acceleration, or braking. It also can happen during steady-state driving due to the engine oil "foaming" as the result of depletion of the oil's anti-foaming additives. And all of this can happen without illuminating the warning light!

Really, by the time you see the light coming on, damage has been done, drastically reducing engine life. We've seen engines fail in less than five years when subjected to this treatment.

While synthetic oil is superior stuff, it's still petroleum-based, just like non-synthetic oil. Its molecule size is synthesized, which improves start-up lubrication and enhances flow. But there's nothing in it that will make it last and protect twice as long as the regular stuff. Enough said about oil, now on to routine maintenance.

Routine is Good

As with oil change intervals, the best starting point for establishing routine maintenance intervals and procedures for your particular vehicle is the good old owners manual. You'll notice that it usually specifies a lot of "inspection" procedures. That is the key to good, low-cost preventive maintenance. Inspect and repair as needed. There is a difference—sometimes a huge one—in cost between repairing after a failed inspection and repairing after a failure. For instance, if an accessory drive belt snaps, will it physically damage anything after it breaks? If the vehicle is driven for long after the failure, will the engine overheat and be damaged? Even vehicles touted to have 100,000-mile tune, trans fluid and coolant change intervals still need to have routine inspections performed. The owners manual will reveal the same needs as other vehicles, such as checking the belts and hoses, braking system, steering and suspension, electrical system (especially the battery), and so on. Besides, remember that the "severe conditions" description may apply and affect the actual time a tune and fluid change will need to be performed.

Conditions

A good rule of thumb for service intervals is this: under "ideal conditions" an oil/filter change and routine maintenance inspection every 6,000 miles. Under "severe conditions"—which describes the conditions most vehicles are operated under—oil/filter change at 3,000 mile intervals. And at every other oil/filter change, include a routine maintenance inspection.

All that is left to cover now is the part where you communicate your concerns and requests with your repair professional. Here are a few tips to that can make this process go easier:

TIPS

> Look at the owner's manual beforehand and get a good idea of what your vehicle is going to need > If you're not sure of the maintenance history of your vehicle, ask for the basic maintenance inspection, and to be advised of any other repairs recommended after inspection

> Be careful of what you ask for. Many people, including some shops, mistake a "tune-up," which mainly pertains to the engine management systems, with a "routine maintenance inspection," which pertains to the entire vehicle.

> If you don't ask for it, and it's not clearly explained in writing, or by the service pro, you probably aren't going to get it. It's not unusual for customers to ask for only an oil change, and upon delivery, ask if everything else is O.K. with the car!

> Listen attentively to the customer service pro, and don't be reluctant to ask pertinent questions about indications of wear and tear to anticipate future preventive maintenance.

> If your vehicle is still under factory warranty, and you wish to have it serviced at an independent facility, make sure that it's licensed to do auto repair. Many states have a Bureau of Automotive Repair, and the shop should have an appropriate license from such an entity on display. Your warranty may be considered void, otherwise. Now that didn't hurt so bad, did it?

Cartalk.com

Transmission Fluid

Transmission fluid is a slippery liquid that acts as a lubricant for all of the moving parts inside your transmission. In an automatic transmission, this fluid also serves as a coolant and a viscous fluid that transmits power from the engine to the transmission.

Changing automatic transmission fluid is best left to a mechanic equipped with a transmission flusher, like this Wynn's Transerve II+, which replaces the fluid more thoroughly than you could achieve with gravity alone.A variety of fluids are used for different transmissions. Automatic transmissions use something called — shockingly — automatic transmission fluid. Manual transmissions use a variety of oils: regular motor oil, heavyweight hypoid gear oil or even automatic transmission fluid in some cases. Your owner's manual will tell you what your transmission calls for.

Should I do this service when it's recommended?Yes, definitely, regardless of whether you have a manual or an automatic transmission.

Manual: Most manufacturers recommend that manual transmission fluid be changed every 30,000 to 60,000 miles. Under heavy-duty use, some manufacturers suggest changing transmission fluid every 15,000 miles.Automatic: Service intervals for an automatic transmission vary from every 30,000 miles ... to never. The typical service interval is 60,000 to 100,000 miles. Changing it more often does no harm.

Why do I have to do this?Manual: In a manual transmission, the problem is not so much the fluid degradation, but rather fluid contamination. This contamination occurs over time as the synchronizers, bearings and gears in the transmission wear out. The resulting metal particles then float around in the lubricant. And we all know that oil with microscopic particles of metal in it does not lubricate as well as clean oil. So if these contaminants are not drained out, they will shorten the life of your transmission.Automatic: Because more heat is generated in an automatic transmission, automatic transmission fluid actually degrades and breaks down with use.

In addition, like in a manual transmission, automatic transmission fluid will also become contaminated with worn bits of the transmission. If these contaminants are not drained out, they will shorten the life of your transmission.

What happens if I don't do this?If you don't change the transmission fluid on schedule, you'll be lubricating your transmission with metal shavings and other contaminants. This will shorten the transmission's life. The result could be a hefty boat payment to your mechanic. In other words, changing your transmission fluid at the correct interval is a good investment.

Is there any maintenance required between intervals?

Automakers have gotten better in recent years about labeling or color-coding dipsticks. The ring on the right is red to match the automatic transmission fluid, the level of which this dipstick measures. The yellow ring is clearly marked "engine oil."Yes. It's important to regularly check the transmission fluid level between service intervals. Letting your car run low on transmission fluid can cause the transmission to shift improperly — or not at all. It also can harm the internal parts of your transmission, which will not be properly lubricated. Unfortunately, you may not hear any noises or have other clues that your transmission is low on fluid, until it's too late. So it's important to get it checked.

Here's how you can check your transmission fluid level:

Manual: Checking the transmission fluid in a manual transmission can be difficult. A few thoughtful manufacturers have included a dipstick, but that's the exception rather than the rule. If you own a car with a manual transmission, we suggest that you ask your mechanic to check the fluid level when your car is up on the lift during an oil change. It takes just a minute.

Automatic: If you own a car with an automatic transmission, your car will have a dipstick for this purpose. Be careful not to make the common mistake of confusing the transmission dipstick with the crankcase dipstick.

For most cars, checking the automatic transmission fluid consists of pulling the transmission dipstick out while the engine is warmed up and running and with the transmission in park. We suggest that you check your owner's manual, however, since some manufacturers may have a different procedure.

Of course, always check your fluid level if you notice a leak of any kind.

Car Talk Tip: Unlike engine oil, transmission oil doesn't burn up. So if you're low on transmission fluid, you almost certainly have a leak.

[da40]

redline mt-90

[qwikxr]

Also, another good one is Penzoil Synchro-mesh, available at AutoZone

[ILikeMy240sx]

I use Royal Purple Max Gear in mine. IVe used MT-90 and I prefer the RP over Mt-90

[nzmoman]

hey i tried to search for this but all i found was how-to's what i am looking for is why..? Why must u change your trans fluid in a manual trans sr20 engine? i have never hurd of such in even vehicles running well over 500 hp. is it something to do with the sr20 engine? i just bought mine and was reading on here and just have never hurd of switing manual trans fluid on a regular basis.. how often do u need to change it and once again why..?

IF you had a baby would you feed once every two or three days, it could live of of that, but you wouldnt do it. You would take care of it to keep it strong and prevent it from being starved. that is more of the issue with people who love their cars.

I think you will find that changing oil is also an extremely easy process. If you are daily driving and not racing your car, you should follow the 20-30k rule.

If you are running the car hard, drifting, drag, or autox then you should do it much more often.

The age of the transmission really is not going to be the reason as much as how hard you use it. When you switch gears metal loses and regains contact. this causes shearing. The oil pulls the shears to the bottom of the transmission so they dont damage gears. they are collected by a metal/magnetic plug.Also, the oil will help to provide a buffer for friction, which will up the temp and allow damage to occur much faster. When oil heats up and cools it starts to go through a chemical change which can make it get gooey and form nasty jelly like clumps. the chemical change is also the reason for the really bad smell that happens with heated and used gear oil.

also keep in mind, the cleaner the oil, the easier it is for the transmission to transfer power. This will give you smoother acceleration and better performance.

And again, keep in mind the difference between routine maint. and performance upkeep. High performance vehicles need to have fluids changed more often to keep their reliability. SR's can handle more abuse than most motors out there with only manufacturers suggested upkeep, but isnt your baby more important to you than that. My Sr vehicles have gotten fresh fluids on a 1500 mile interval. Gears done every 5. Not because I had to, but because they are my personal investments.