Redline D4 Transmission Fluid in '99 LC

[calskibum]

Just had my '99 LC transmission serviced by drain & fill with Redline D4 transmission fluid. I've never used synthetic tranny fluid before and noticed something interesting with the D4. Usually after driving 10 miles or so on the freeway, the tranny fluid level is sufficiently warmed up to measure full in the hot range on the dipstick. But with the D4, after driving 10 miles on the freeway, the fluid level didn't even reach the hot zone on the dipstick. After 20 miles on the freeway, it then reached the middle of the hot zone. I didn't check to see if driving more after that would cause the fluid level to measure higher on the dipstick.

Is this due to the synthetics' resistance to heating up and that it really takes driving longer to properly warm up the tranny fluid to accurately test the fluid level? Or does it mean that I don't have enough D4 and need to add more? How much fluid difference is there between the low and high marks in the hot zone on the dipstick?

 

[Tinkerer]

calskibum, please tell us how you like D4 in your tranny, if you notice any difference, etc.

Regarding your questions:

1. Do you know for sure the cold vs. hot level of the previous fluid, and also the cold level of the D4? (Maybe D4 fill amount was half a quart less than the previous fluid?)

2. What was the previous fluid? (mfg/brand, type, etc.)

3. Was "drain & fill" a complete fluid change, or drain pan only? (Draining and refilling only the pan content does not change fluid remaining throughout the system including torque converter etc.)

I am using D4 in three other vehicles (02 Accord, 04 Odyssey, 98 Avalon). I first tried it in the 02 Accord to remedy a slow 1-2 shift when cold and gear noise, and it does help - the 1-2 shift is better and the gear noise is much reduced.

Would have already changed to D4 in the LX too, but it was not too long ago I changed it to Maxlife, before I started using D4. I'll change the LX to D4 when it comes due.

(02 Accord is known for tranny problems including 1-2 shift and overall high failure rate, and uses straight cut gears hence the noise. I am hoping the D4 will enable a decent life expectancy from the tranny.)

 

[calskibum]

Tinkerer, I'm not sure if I feel any difference with the D4 vs. what was in the LC before, but I do feel better knowing that I get a bit more protection now with the synthetics. I'm not sure what type of tranny fluid was in there before since it was done by the PO. I've had the LC for about 10 months now and had already put over 20K on it. Even though the tranny fluid still looked fresh, I figure I change it just to be on the safe side since I'm not sure how long it was in there before I bought it. Along with putting D4 in the tranny, I also had Redline 75w-90 gear oil put in the differenctial and transfer case.

I checked the tranny fluid level cold today and it was halfway in the cold zone. I checked it again after driving 100+ miles on the freeway and it was 40% in the hot zone. I added another 1/4 bottle of D4 which brought it up to about 65-70% in the hot zone. I'll get another reading tomorrow after driving 100+ freeway miles to see what the final level is.

After looking into the fluid level further, I recalled the shop stating that they put in 3.4 bottle of the D4 after the drain and refill. The owner's manual states that it would take up to 3.7 quarts after a drain and refill. When I looked on the bottle, it said each bottle is .946 quart, which makes 3.4 bottles to be 3.22 quarts. I think this might explain why the level is not at the full mark. I heard bad things happen when tranny fluid level is too high, so I'm inclined to keep it in the 70-80% of hot zone to give it a bit of margin for further expansion. Am I wrong on this approach or should I fill it to the top of the hot zone?

 

[NMuzj100]

I heard bad things happen when tranny fluid level is too high, so I'm inclined to keep it in the 70-80% of hot zone to give it a bit of margin for further expansion. Am I wrong on this approach or should I fill it to the top of the hot zone?

This is a good plan. With just a little too much fluid I had some shifting problems. I think you'd be fine at 100% if you were really measuring hot. (uncomfortably hot to touch).

The difficult thing in the 100 is to really get the transmission temps up for a good max volume measurement. At interstate speeds the transmission fluid cooler will keep it pretty cool. Try some mountain climbing in Low.

 

[calskibum]

This is good info. I did not know that highway driving actually cools down the tranny. Now I wonder if at 70% full after freeway driving is actually high. Is there another way to get the tranny to the proper temp to check the fluid other than hill climb since I won't have the opportunity to do that for a while?

My '99 LC did not come with the tow package. I read that all '99 LCs come with tranny cooler whether or not it has a tow package, but I also read somewhere that's not the case. Can you advise what the tranny cooler looks like and where I should look to see if mine has it? Anyone has a pic of it would be greatly helpful.

Thanks.

 

[Musky]

This is good info. I did not know that highway driving actually cools down the tranny. Now I wonder if at 70% full after freeway driving is actually high. Is there another way to get the tranny to the proper temp to check the fluid other than hill climb since I won't have the opportunity to do that for a while?

My '99 LC did not come with the tow package. I read that all '99 LCs come with tranny cooler whether or not it has a tow package, but I also read somewhere that's not the case. Can you advise what the tranny cooler looks like and where I should look to see if mine has it? Anyone has a pic of it would be greatly helpful.

Thanks.

If you open the hood and look down at the front of your radiator you should notice like a mini radiator. If yours has the mini radiator that is your tranny cooler.

 

[Skidoo]

FYI: You are looking at 17 qts to change all the ATF. Pan only holds small amount, between cooler, hose and rest of trans a lot more in there, so still running mostly old ATF.

 

[calskibum]

Wow, 17 qts! I'm hesitant to do the flush so I guess I'll have to do quite a few more atf fluid changes to get the synthetics protection.

 

[Tinkerer]

I did the ATF cooler hose discharge trick:

Drain pan, remove it & clean out sediment and magnets, replace filter (not really necessary), reinstall pan with new gasket/compound. Fill pan with 3.x quarts new ATF.

Remove ATF hose connection downstream of cooler. (Or both if you don't know which one that is.) Using clear vinyl hose as necessary for temporary drain hose, set up to discharge ATF into empy gallon milk jug.

Then several iterations of:

Start engine, watch until 2 quarts filled in milk jug, stop engine. (Don't run ATF dry!) Add 2 quarts to tranny. Repeat, using empty milk jugs as necessary.

Finally, top up the tranny pan with ATF as necessary to bring to correct level. Reinstall ATF cooler hoses.

*******

This will utilize the tranny pump itself to pump old fluid out and replace it with new fluid pumped through the torque converter and rest of the system. If you want to be really thorough you can shift P>1>P while pumping, pausing a second or two on each gear selection. Takes a couple more quarts new ATF than the total capacity to be sure of getting all the old fluid out.

Thanks to MUD'ers for posting this method, I have used it with good results on all four of my vehicles now. Its messy but easy, provides a complete changeout, and kinda fun to watch people's faces when they ask what you are doing.

 

[calskibum]

Tinkerer, thanks for this info. It looks to be a great project for me to think about.