How long or how many average miles are people getting from the c5 auto trans.?

Is the 4L60E holding up ? I bought my corvette (98) with 100kmiles...shifts great. no issues right now.


are people dropping the pans and doing a drain and fill?

 

That is always the $100,000 question and the answer is always... "it depends."

In a perfect world under perfect conditions the transmission can easily last several hundred thousand miles. However, "real world" conditions make a huge impact on automatic transmissions. Things like; fluid condition, driving habits, idling long times, trans fluid temps, hard starts...etc.

Probably the biggest unknown for our hobby are the modifications that we make to our engines. If you build your engine adding another 75-100 hp and don't make any modifications to the trans, you will clearly begin to push the edge on its design capabilities reducing life.

Now to answer your question more specifically, if you are a (mostly) sane driver, have not over built your engine and keep up with appropriate maintenance, getting 175-200 is very realistic.

 

good answer.

Im not going to push this one.....I have a 680hp mustang for wild $hit

the vette is a cruise with the occasional right foot mash------i mean who doesnt run a 1/4 mile hard every time out for a ride? stock power though.


I bought the car with 99k on it...shifts nice--seems solid. But I KNOW auto's are funny sometimes when you change the fluid.....i was wanting to drop the pan and through a gasket on it...but my buddy looked at me and said...i dont know..........

 

I'm wondering the same thing about a trans drop and fill. Although mine isn't at the 99k mark (mine is 40k), it's still 20 year old oil in it. But I've always heard NOT to change automatic transmission oil as it can lead to problems.
What's the real story on our cars?

 

Be not afraid and use GM spec fluids and filters. Don't get fancy with aftermarket claims and gizmos. Keep it simple and reliable.

 

I bought my 98 with 87K miles. I did install a transmission cooler around 95K and when doing so a little fluid came out the lines and it was a dark red color. I assumed it was probably changed at some point. In the summer time heat after an hour driving I would see temps in the 220-230 range. With the cooler I have not seen temps above 210 unless I'm really driving hard. Around town I cruise in 3rd (D) instead of OD as well. I also had the car tuned and the transmission was tuned at the same time. Shift points, rev limiter, converter lock up and some other things were changed. Car drives and shifts much better compared to stock. I'd say it would probably be a good idea to invest in a cooler either way, you don't want the trans temp getting too hot although I think the manual says up to 230 is normal.

 

I bought my car in 2009 with 75,000 miles on it, totally stock. Since then I have put another 43,000 miles, 24 road course track days and approximately 6,000 upshifts from 2nd to 3rd at WOT on track as well as 6,000 manual downshifts on track.

Because I track the car I change transmission fluid and filter more frequently than most. Five fluid and filter changes so far (drain and refill). I always use Red Line D4 full synthetic fluid. Keep in mind that a drain and refill with a stock transmission pan actually changes about half the total fluid in the transmission. The rest is in the torque converter and other works.

Never anything more than a slight clutch dust in the pan.

Over the years I got faster and transmission temperatures on track rose. In response, again over the years, I first installed a B&M finned aluminum transmission pan; a DeWitts radiator with engine oil and transmission coolers; Improved Racing engine oil thermostat; auxiliary transmission cooler in front of the condenser. At present I am thinking of changing the existing 20,000 GVW auxiliary cooler for a 40,000 pound GVW cooler because I have had to come off track when transmission temperature hit 250. 250 is just a personal limit.

In 2016 I had to replace the 3.15 rear drive so I had a 3.73 installed. Faster.

Stock Horsepower.

Getting ready for track day 25.

 

If you keep up with the maintenance, drive sensibily, and do not make any major power enhancing mods, your A4 should last you 150-200K. Of course, that could obvioulsy change since it is a part subject to wear, tear and premature failure.

 

I got my car at 105kmiles, without detailed maintenance history + crash. One of the service, after driving it 10kmiles myself, was a refresh of trans and diff fluids, just because fluids are getting old, hot, will oxidise and lose lubrification properties a little. No gasket, nothing else…and this will probably be the last time I do it for the car…or I may, if I still have it, do it in another 100k.
BTW engineers have probably never tested nor engineered the car or it’s components for more than 10years of usage.
my 2 cents.
TCFS

 

I serviced mine after I bought the car with history unknown.112k miles at the time . No issues.

 

First thing I did when I bought my vette was change the transmission fluid. There is no dipstick so no way to tell what condition it is in without pulling the plug/pan/filter. Do it, and use what GM says to use. No worries.

 

I didn't know this... Thanks for the tip...

 

Original owner of my 2004, almost 75,000 miles on it. It shifts fine, 340 wheel horsepower and newly installed 3.73 gears and 3200 converter. When they did the gears last year, they did a trans filter for me, all new trans fluid. When it breaks, I’ll get a new trans.

 

What if you wanted to install a better Trans cooler, what would you look for in a Transmission Cooler, I put on on my pickup, but that was a long time ago and it was for my pickup truck used for towing. I never thought of one for a sports car ?

 

"What if you wanted to install a better Trans cooler, what would you look for in a Transmission Cooler, I put on on my pickup, but that was a long time ago and it was for my pickup truck used for towing. I never thought of one for a sports car ? "

I look for the gross vehicle weight rating (GVW, sometimes annotated GVWR). The highest I have seen is 40,000 pounds GVW, but larger units may exist. I believe the flat plate, parallel flow, low pressure drop coolers are more efficient and provide the greatest flow. Also use hoses as large as can be accommodated by the cooler fittings and short as possible hose routing.

Flat plate 40,000 GVW:

Tube and fin coolers have higher pressure drop and lower ratings, Here is one with GVWR 18,000 pounds:

 

I put one of these in my 2 Jeeps and plan on one in my 2K Coupe as well. It has 113,000 on it and shifts great, however it is hot here in Florida and I have already witnessed 225 degrees trans temp stuck in traffic and it's not even summer. In my off road playtoy it dropped the trans temp 40 degrees when beating it in the sand.
https://www.trucool.com/products/tru-cool-max I used the biggest one, the LPD4739 though for the Vette I won't get the cold weather bypass, the LPD47391

 

I not seen over 255°f on dic after 20+ minute track sessions with the stock rad and ~230 water temp. It seems to get up to 245 or 250 and "level off" there. I have the dewitts to install with eoc+toc expecting the water will not go over 200 also expecting some corresponding reduction in trans temps as well.

I am more concerned about engine oil temp as it never "levels off" without a cooler like trans temp does so I have the one with eoc and toc.

I've been told that 300f (actually 150c) is the upper limit for trans or hydraulic fluid. Also I think there is warning bong on dic over 280... If you keep going after that you are on your own.

 

Trans coolers are awesome. I have one. Transmission temps don’t even go over 190 in summer heat, 3.73 gears and 3200 stall.

Spring, fall, winter when it’s about 40 degrees out, transmission temps maybe hit 150-160 after an hour of driving.

HPDE event, I haven’t seen over 210.

without the cooler, I was at 250 at an HPDE event, put it in OD and was easy on it to cool it off.

A shop installed mine, I don’t know how large it is, but it works.