: New Guy to Northstar and their General Maintaince

06-22-11, 07:59 AM
Good morning all... I am the new owner of a 2002 Cadillac DeVille(DTS) with the 4.6 Northstar and 4T80E Tranny... The car has a little over 96,000 miles. I am an avid gearhead and have done all my own engine/drivetrain work on all the vehicles I have ever owned, including engine/transmission rebuilds. There hasnt been a job(yet) that I havnt felt comfortable doing, but this is the newest vehicle I have owned and I have a couple questions regarding maintaince regarding maintaince on the Northstar. For the oil, I plan on using 10W30 Synthetic Oil such as Mobil 1 and a Wix Oil Filter... Now on to coolant... What kind of coolant(color) does the Northstar use and does it need any special GM additives? Also, what is the recommending flushing schedule? Next is the transmission. What kind of tranny fluid does the 4T80E use? Can I change the filter or does the case need to be split? If it needs to be split, I will flush the tranny more often than if I can change the filter. Does the Cadillac need a special power steering fluid? Next is Tune Up. Are the spark plugs hard to get to and do I need to use platinum plugs? Finally, as I said earlier, the car has 96,000 miles and was owned by an elderly couple who took very good car of the car, is there any known issues that I need to be aware of, or any issues that are known to pop up around 100k miles? Thanks for the help and I hope to be a part of this freindly community.

06-22-11, 10:15 AM

First thing i'd recommend is to get a factory service manual, or an Alldata subscription, two best investments one can make for the DIY'r. As for sparkplugs, and coolant id stick with what GM specify's not sure what they recommend for the 02 DTS

06-22-11, 10:30 AM

FSM or alldata, etc is a MUST for a DIYer on these cars - burn any haynes or chiltons manual you have for N* vehicles

do yourself a favor and read the 'technical archive (http://www.cadillacforums.com/cadillac-tech.html)' (for future reference, it's at the top of all the site's pages in the black header)

also read as much as you can in this forum (especially the sticky threads at the top)

and also check the Tech Tips (http://www.cadillacforums.com/forums/cadillac-tech-tips/) forum for common issues/repairs

almost any question that you have will have already been asked and answered before so before you post a new thread about something please search
(you can use the site's built-in search or google with the site:cadillacforums.com modifier)

get yourself up to 10 posts (browse around and join some discussions) so you can unlock the PM features and link/picture posting privileges

and finally, let me know if there's anything i can help with

welcome aboard :wave:

06-22-11, 10:49 AM
OK............In order:

Your engine has roller cam followers and the recommended oil is 5W-30 in whatever type floats your boat. Use a WIX 51522 filter and prefill it. The engine takes 7.5 quarts with filter, no more. This will bring the oil level to halfway up the dipstick hashmark. Any higher is overfilled and the engine will burn off the excess in a hurry, leading to false indications of oil consumption..... GM TSB on this.

DEX-COOL every 3 -4 years. Coolant to halfway up in the reservoir, COLD. No higher. There's a fill arrow on the reservoir top/side. Cooling system is also like nothing you've ever worked with. Steep learning curve.

DEXRON-VI. Pan drop or cooler line pumpout is all that's required. About 8 - 10 quarts. No filter except at complete overhaul. Bone dry, 15 quarts. Complete transmission drop and disassembly, 12 quarts. Typical fluid exchange, 8 - 11 quarts. Transmission is a dry sump unit and there will be no fluid on the stick with the engine off. Fluid level is checked with the engine running in P, hot, on a level surface. (Not sure about the DTS, but the engine will not run with the air intake resonator removed [if you have one] - plug the hole in the rubber flex intake duct.)

GM Power Steering fluid.

Yes, the plug cassettes are a bitch. AC Delco #41-987 platinum plugs ONLY. Don't try to "make it better" You'll regret it.

Issues and maintenance ????? It's all in here and you need to study. There is a LOT more to your car than you know. Read the sticky threads at the top of this forum page - you'll need a couple of them for constant reference. Your car has its own built-in code reader/scanner, for starters.

Remember: When all else fails, read the owner's manual.

Click on the pictures to enlarge.

06-22-11, 12:07 PM
When you change the trans fluid, remember that there is a hidden drain plug for the side cover when you drop the pan.

06-23-11, 02:37 PM
Thanks for the advice guys... I will defenitely read the above mentioned information... I look forward to learning all I can about the Northstar and its capabilities.