Fresh Differential Fluid

[ceningolmo]

Ok... I just changed the diff fluid.

I'm not sure if you all are aware of this but fresh fluid actually makes the Q drive smoother. I know, I know... crazy talk. But, hear me out. As it turns out, if you go out and get the BG transmission fluid flush with synthetic ATF (amsoil) and then change out the diff fluid with synthetic (M1) your Q will drive, shift, and just generally feel smoother.

Fresh fluids? Why, that's crazy talk you say!

Seriously, its well worth it.

On a side note. When you open up the two plugs on your diff and, I don't know, about 2 oz. of fluid drain out you can probably assume your diff has not been running optimally. Additionally, if the fluid that does come out is pitch black and reeks like a dinosaurs ***...the fluid was probably short of ideal.

On another note...planning ahead to have hose of appropriate weight and diameter will make the job much easier. Also, when ALL of the experts on your favorite site (nicoclub.com), as well as several of them via conversations on AIM, recommend that you warm the fluid first in order to help it flow easier... well, ****ing do it you moron! No matter how "not thick" the fluid looks, feels, sounds while it is in the bottle... I assure you, it is in no particular hurry to go through a hose and in to your diff.

On yet another note...if you happen to be a moron. I'm not going to verify whether I am a moron, but I am going to suggest that it is a possibility. If your moronocity happens to leave you with non-warm fluid (and, by non-warm of course I mean ice ****ing cold since I left it them sitting on my garage floor while it is 40 degrees outside) and a hose that is really long and slightly too narrow to properly carry the fluid, here is a solution to your problem.

Solution1. Trim nozzle of bottle and attach hose of inappropriately small diameter.2. Crawl under your car and hold the hose in place so that it doesn't fall out of the open plug in your diff.3. Have your wife STAND on the bottle of diff fluid thus forcing it through the hose and in to your diff.4. Spill at least 1/2 quart of fluid on your garage floor, hands, hair, and potentially wife.5. replace plugs, start car, drive around with large smile on face.

[maxnix]

Some things are better done in Texas.

At least you don't have to use the wide spread 70W-140 to cope with the Texas summers.

Fresh fluids (and filters) are cheap maintenance.

[elwesso]

i used 75w140 M1 GL5 in mine...

How did the magnet look on the bottom plug?

[goody90q45]

Been there, done that, about 2 weeks ago. I put Valvoline synthetic in but will be switching to Amsoil very soon. My fluid was very black and thick also and twice as much went in as came out. Go figure.

On the plus side, the differential does run quieter and the car does seem to shift smoother. On the negative, the differential is probably the easiest fluid to flush. I'm in the middle of draining/refilling the PS fluid with Amsoil ATF right now. A few more flushes over the next couple of weeks and It'll be done. Have fun!!

[qship96]

If both transmission & rear are done every 25-30 thousand miles they both come out looking near new.I have yet to see any buildup on diff plug magnet using these change intervals with synthetic {184,379 miles}

[Falkdesigns]

When I just did my oil change last weekend (or was it the weekend before...) I flushed the PS with Amsoil ATF, and the diff with Amsoil Slip-lock and the Severe Gear 75-90. Car rides just like before, but at least I know all the fluids are good now.

[Q45tech]

Just budget for a new one [good low mile unit] every 250,000 miles.....the bearing usually go.

The diff has highest friction from a start until around 10 mph so new fluid [less thick] can make the launch feel better.................diffs are optimized to have the lowest friction around 500-600 output rpm [50-60 mph] to help with MPG.

[qship96]

[QUOTE=Q45tech]Just budget for a new one [good low mile unit] every 250,000 miles.....the bearing usually go.

i dont think I will ever replace the diff,as I will unload the car at 250-300,000 miles for a 2-3 year old used lux/performance sedan and start the process again.

[ceningolmo]

Another note that I forgot from unnecessarily long initial post.

1/2" drive is required to remove the two plugs. 1/2" ratcheted drive isn't required, but is highly recommended! Since the "bolt" mechanism is 4 sided, rather than 6, you can only lock in your drive at 90 degree angles...thus, your angle options are severely limited within the limited space for the upper plug.

[maxnix]

Just budget for a new one [good low mile unit] every 250,000 miles.....the bearing usually go.

i dont think I will ever replace the diff,as I will unload the car at 250-300,000 miles for a 2-3 year old used lux/performance sedan and start the process again.

Interesting theory that assumes you can find a car as good as a properly restored G50. More than a few who had that theory were less pleased when they traded up to an F50 when after a few years of ownership all the whiz-bang gee-gaws lost their novelty. The G50 is an extremely honest car.

Don't think I will ever get to a car that reports on me via hidden memory chips.

[ScottJackson]

For sure, there's all sorts of electronic doo-dads that new cars are being REQUIRED to have... that I despise. In that light, even though a '67-69 restored camaro may not be worth $30K and people would hate to see me driving it in winter storms, it would still be worth it to me. The G50 has a little more gizmos than I'd like and my 540i is about the same in that department. And even though the new corvettes have cheap interiors, they're nice and simple, which I'd much rather have than even a Bugatti Veyron. Although, if I could afford to have a Veyron (especially as a daily driver) then I could probably afford to just junk it and buy another when the leather starts peeling and little things act up. Oh yeah, I have one of those little suction tube things that looks kinda like a grease gun for stuff like diff fluid. Works great.

[Jesda]

Damn, that and a transmission cooler are two things I keep forgetting. The Q's been trouble-free so I keep forgetting about regular maintenance.

[goody90q45]

The Q's been trouble-free so I keep forgetting about regular maintenance.

Tsk. Tsk. Tsk. Wait till Brian sees this. He'll have your pants!

[elwesso]

Damn, that and a transmission cooler are two things I keep forgetting. The Q's been trouble-free so I keep forgetting about regular maintenance.

you could knock those 2 things out in about 1 hour... TOPS...

in the eariler G50 (90-92, with single cooler) you dont have to even cut new hoses... when i installed a cooler on a 92, i just unplugged the hoses on the stock cooler, plugged them into the external transmission cooler, and put it in between the radiator and condensor... DONE!!! may need to take the radiator out, or at least loosen it to get enough room to put it in....

[Jesda]

I could do it... but working on the Q stopped being fun after I learned everything. I'll make an appointment at the dealer.

Mike: I installed some of that 3M heat shield stuff on my MAF connector. Neat stuff! One of these days I want to put it around the injector harness connectors.

[goody90q45]

Mike: I installed some of that 3M heat shield stuff on my MAF connector. Neat stuff! One of these days I want to put it around the injector harness connectors.

Good stuff. When used properly it will go to the moon and back!

[DrewQ45]

I could do it... but working on the Q stopped being fun after I learned everything. I'll make an appointment at the dealer.

Huh? You think it's more fun fishing out your wallet at the dealer??? When can I bring my Q over? I'll give you all the fun you need.