Installed Diff. temp gauge - Page 3

sc186 · 04-11-2006, 12:40 PM

The diff failures would be caused by overheating if they were a bearing failure, but they are( as far as I know) spider gear failures. I doubt that the temperature gradiant between the finned and steel cover would make the powder-cast spiders fatigue enough or ductile enough to fail.

Just my .02

Oldfordowner · 04-11-2006, 06:25 PM

One of the problems with add-on electric gauges is that they have no regulated voltage source. Add a voltage regulator chip (12v regulated) that is available from Radio Shack. One lead goes to power source, one is grounded, and one goes to the gauge + terminal. Insulate the leads with shrink wrap.

This will stop the surge in voltage from idle to full alternator output that may be causing the surge in temp readings. My diff runs only 175 after a freeway run and barely hits 200 degrees when towing. I use a ray-tek I/R gun to read temps.

SOCALTITANKC4X4LE · 04-12-2006, 05:45 PM

Thanks Old, I will install 12v regulator and then post with results.

SOCALTITANKC4X4LE · 04-13-2006, 11:28 PM

Ok, Oldfordowner, I installed 12 volt regulator chip as you suggested, and now the temp stays at a constant 140 Degrees, even when I accelerate. So I thank you and all the others for your ideas and suggestions. I will post if and when I tow, to see if temp. increases.
BTW the GlowShift meter looks so cool at night, it changes to 7 different colors just by pressing a button on the gauge.

SOCALTITANKC4X4LE · 04-14-2006, 01:20 PM

Pic of Temp. gauge.

SOCALTITANKC4X4LE · 04-21-2006, 09:41 PM

I just finished installing the Trans. temp. gauge next to the diff. temp. gauge. The trans. temp. is running at 140 deg.

Titanminator · 12-20-2006, 04:36 AM

Quote:

Originally Posted by SOCALTITANKC4X4LE

I just finished installing the Trans. temp. gauge next to the diff. temp. gauge. The trans. temp. is running at 140 deg.

can you post pics of the finish product on your dash. trying to get ideas to where I can place the gauges.

KYDeepwater · 12-20-2006, 06:03 AM

240 degrees will not cause any degradation (oxidation) of the synthetic gear lubes. It could cause some accelerated reaction of the sulfurized additives to the metal, but this is expected to have the lubricicty additive do its job.
I have had the PML cover since early 2005, and a number of times, after towing our 4,500 + pound boat and four people two solid hours without any stopping, I could place my hand on the side of the cover and leave it there without it feeling too hot to touch. The 140 weight gear oil also will not thin out as much at this temperature, which will result in a thicker oil to fill the voids between the gear teeth and improve lubrication. The spider gears, and some of the other gears, are powdered metal that are supposed to be heat treated to around 1,400 degrees to properly harden the gear teeth. Some of the past failures reported here that had photos showed the spider gear face, most of them looked as if they were "melted" away, which would indicate improper heat treating. Even a few hundred degrees less than specified will make a huge difference in the hardening of the gear. My guess would be a few of the gear parts were not properly treated by Dana, and ended up in some of the rear diffs. QC ain't what it used to be, especially in a company that has been on the edge of bankruptcy the past few years.

Yahooligan · 12-21-2006, 05:27 PM

I just got done towing a 5000lb TT (23') about 400 miles from CA to AZ, after running 55 on the freeway for quite a distance, a lot of uphill, and then stopping for gas, the diff cover was only warm to the touch and the diff housing was hotter but not "hot." I could keep my hand/fingers on it for multiple seconds before it felt "uncomfortable."

As for OK temps, 200-290F I would consider to be OK and normal, with the higher end being under heavy load. In order to be API certified for their specific rating, such as GL-5, lubes and differentials are tested at different loads and speeds with temps ranging up to 295F. If there is any damage to the gears or bearings, the lube fails certification.

Titanminator · 12-25-2006, 08:27 AM

Quote:

Originally Posted by SOCALTITANKC4X4LE

I wonder if the Nissan Diff cover extends out far enough so that the sending unit does not touch the gears. The PLM cover is 2 inches deeper than Nissan cover.

Can we install a sending unit to the stock aluminum diff cover?