Recommendation for radiator replacement

[SFBayQ45]

Since this didn't still up many responses in the Infiniti General forum, I'd like to see what kind of responses I would get from here. A new one from Joe @ $397 is hard to swallow, so I'm looking for an alternative that better fits my budget.

azskygod - I believe you recently replaced yours with an aftermarket, so how's that new aftermarket radiator and would you recommend it? If so, could you provide the contact info?

q45tech - I remembered one of you many posts suggesting that you would only go back to OEM since the custom-made radiator you installed wasn't worth it. If that's the case, would you recommend me to stay clear of all aftermarket radiators?

hitman - I think you just installed a new radiator as well during this past summer's heat in AZ. Regardless of which type you used, what are your personal thoughts?

everyone - Any input/feedback would be greatly appreciated, so please feel free to chime in...

[mersidoe]

I got an aftermarket radiator at a small independent shop recommended by the dealer last summer. No problems, no complaints.

I couldn't bring myself to buy one from "radiators R US" on the internet.

I have a J30, but it was about $200 for the radiator, and $100 installation. Hopefully I'll never need another one, but I would go back there if I did.

[DAEDALUS]

Post in Infiniti General or email those guys directly. I don't see Greg or azskygod in here much. I'd go OEM myself, but I plan to keep the car for at least another 10 years, plus I cross the desert every now and then. In the bay area an aftermarket unit's (probable) reduced capacity is less of a concern than in, say, Phoenix. Consider driving habits and what kind of trips you'll be taking in the car.

A common mistake to guard against--make sure the radiator comes with the right pressure-rated cap. Stock rating is 11-14 psi. If it's lower it'll reduce the boiling point of the fluid and cooling efficiency. If it's higher you could burst the heater core.

[tangalora]

I have a (maybe unrelated?) question regarding the radiator/transmission cooler?

I've never upgraded mine (1990 Q45) and sometimes (when the car was running) on a hot day, I could "smell" what seemed like transmission cooking just a little when I shut off the car. It wasn't that sickly sweek cooked coolant smell but that slightly burned transmission smell.

Somewhere I "heard" a lot of folks do a transmission cooler upgrade.

What is that?Since I have to remove my radiator anyway (for a chain guide R&R) ... should I look to doing something with that transmission cooler upgrade somehow? Or is this a dumb question?

[DAEDALUS]

No better time! I assume you're running Mobil1 ATF?

http://www.ozop.net/trannyclr.htmhttp:/ ... d?id=31990

[tangalora]

No better time! I assume you're running Mobil1 ATF?

Wow. Excellent references. I was especially surprised to see aftermarket coolers recommended.

Since I may remove the radiator anyway (to give more room for the chain-guide R&R documented at http://www.nicoclub.com/zerothread?id=92996), I might consider adding the transmission cooler.

Mobil 1?I don't think I've ever put an ounce of transmission fluid in this Q45. I've checked the level probably once every few years. Should I be more diligent?Should I replace the fluid at some future date (when the car is put back together from the oil pan R&R documented at http://www.nicoclub.com/zerothread?id=77266)?www

[Q45tech]

Depends: My Griffin all aluminum higher capacity custom unit has 110,000 miles [5.5 years] and still looks brand new inside and out........thicker metal everywhere. $700 was a good investment

And the end to summer problems with twice year changes in AF density and distilled water [summer 25% winter 50%] and watching PH.

Study the AC condenser and rubber foam and flaps [air surround] for blockages and air leaks that reduce efficiency!Every single degree F counts when you are in Summer traffic.

Don't skimp or change a cheap one every few years.

[AZhitman]

Alora - transmission cooler for the Q is the B&M #70268, about $50 from Summit Racing.

I have no doubts that you can install it on your own, as you're more of a gearhead than most of us! But, just in case, there are several transmission cooler installation threads here - we can walk you through it!

[elwesso]

Check the writeup on Q45.org.....

[Q451990]

Here's my B&M with the radiator removed. The front of the radiator is facing you. I placed it there because it fits under the metal A/C tube and it's right in front of the aux. fan, hopefully for better cooling in extreme heat situations.



Heath

[tangalora]

After reading all the referenced posts, I really don't understand exactly WHY people feel the need to add an additional Hayden or B&M 70268 to suppliment or bypass the original transmission heat exchanger in a 90-series Q45.

Of course, I can infer the problem was the factory heat exchanger was inadequate ... but what particularly was the sympton or damage that clued you into the fact you need a better transmission heat exchanger (besides a hot shift lever)?

I do see statements such as "The factory cooler actually works as a heater in the summer when the coolant mixture is warmer than the preferred operating temperatures for the transmission. " But what is the symptom if the transmission fluid gets too warm in the summer? And how frequently did this symptom occur in 90 Q45 models?

Interestingly, there was little mention of the automatic transmission oil cooler (other than a minor reference to the AT oil cooler pipes) in the AT section of the 90 FSM, so, I am looking to Nico for further guidance.

It seems the B&M 70268 & 70264 (better cooling) from http://store.summitracing.com (store.summitracing.com) are referenced the most:70268 Fluid Cooler, Transmission, Plate Type, Black, Aluminum, 7 1/2 in. x 11 in. x 3/4 in., $45.88 70264 Fluid Cooler, Transmission, Plate Type, Black, Aluminum, 6 in. x 11 in. x 1 1/2 in., $49.88 but that was on a mix of model years.

Do both fit nicely in the front-of-radiator-after-condenser location on a 1990 Q45?

Also, every once in a while an "external filter" for the transmission fluid was mentioned in passing. Is there such a thing (I thought the transmission oil filter was inside the transmission)?

Another question that arose is whether there is a power-steering heat exchanger or not. It was cryptically referenced in the threads but I don't see anything about it in the ST section of the 90 FSM ... so I'm not sure if it exists.

[Q45tech]

Simple just measure the ATF temperature coming into cooler and returning to transsmission IF ever above 176-190F the ATF gets degraded.

Don't assume the transmission sump temperature tells much, as the TC output temp [going into cooler is what counts to see what the PEAk EXPOSURE temp was!

The cooler side of the radiator coolant should be below 170F.......almost impossible in Summer traffic.

Worst case is often highway cruise in 4th gear trying to pull a slight incline with AC on............slipping TC and low AT pump speed.............peaks are > 250F.

As at 70-80 mph [unlike Japan max speed of 55 mph] the transmission doesn't need to downshift [to pull a slight up hill] as engine torque is higher.

[elwesso]

T.. The cooler is integral with the radiator...

If the engine is supposed to run at 176 (few probably do) AT THE THERMOSTAT HOUSING (which means coolant should be fully cooled by then) its easy to see why the stock setup is inadequate... I think it might be safe to say that the way they designed it from the factory the transmission would overheat from day 1, in warm temps... However, the transmission was only supposed to last 100k...

Heres a picture of the transmission cooler in my Q, not yet hooked up.

[tangalora]

I (mostly) trust(ed) the Infiniti engineers so I guess I'm just surprised something as obvious and calculable a design concern as the transmission oil temperature would have been bungled in a Q.

I mean, it's soooo easy to calculate in theory & to test in their early prototype cars.

I guess I'm just having a hard time seeing how they could have missed this in the design stage; then again, my 90 Q45 transmission (at 135K) is still working without complaint (except for a whiff of burnt something or other after a hot haul up a steep mountain pass) so I shouldn't diss them as they met their 100K constraint just fine.

P.S. I opened a separate thread specific to the proper removal of the radiator (so as to not clutter this & other related threads with those gory details).

[tangalora]

... just measure the ATF temperature coming into the transmission cooler ... above 176-190F the ATF gets degraded

Very interesting. This implies is my stock ATF has been degraded (looooong ago). I'll immediately take your good advice & replace the 9 1/8 quarts of ATF as one of the first items after my current repair. I wish I had done it sooner given what you've noted.

Since I don't know much by way of personal experience or professional training (and since I rarely have 1:1 access to professionals), I generally defer to test organization seals of approval for most fluids I purchase.

For example, for motor oils, gear fluids, & brake fluids I just look at the API & DOT service designations (i.e., SH, GL-5, & DOT4) which allows me to instantly compare "quality" among brands. Normally I use any brand of coolant (my assumption being that they don't print quality numbers on ethylene glycol 'cause it's the same no matter who makes it). I obviously saw the recommendation for Mobil1 but the FSM merely specifies "Genuine ATF*1 or equivalent Type Dexron™".Q: Is there an ATF "quality" specification printed on the container I can trust?Specifically, does the Mobil™ brand of ATF carry a "service quality" designation somewhere on the package from a test organization (or do folks recommend it mostly from word-of-mouth or personal experience).

[qship96]

not just Mobil atf,but specifically MOBIL 1-synthetic ATF-Amsoil & Redline also make excellent,abit more expensive fully syntheic ATF.