: How hot does your differential get??


Swampgoat
01-29-2006, 07:12 PM
I noticed after the BMP event last weekend that my diff was quite hot. I had done a dozen or so passes, with a very spirited 75-90mph run home of 70 miles afterwards. First time to the track on the Kaaz/3.91, but over 1000 miles. About 600 on the oil and 4 ounces of Transx modifier.
I put Swampgoat up on ramps right after I got home to check everything out after a track-day, make sure nothing loose or leaking and noticed the diff was hot...like real hot, 1 or 2 seconds touch max.
I asked Kurt down at Difftechnics, and he said that, yeah, they get good and hot, no worries!!
So yesterday, a week later I run 30 miles at highway normal (75), and a little stop and go and noticed a bit of whine, but only with power on, clutch in, whine gone, back out, whine. Housing temp probably close to or over 200.
Cooled car for 3 hours while visiting family and left, no whine. By the time I got home, very light whine again. 2 second touch max on the housing. Probably about 150degrees
Hmmm, I changed the diff oil today and put 7 ounces of friction modifier (CRC transx) in and figure I will go see how hot she gets, or if she whines.
My Kaaz/3.91s are just passing 1500 miles. Working flawlessly. Went and threw some figure 8s and a few decel torques to see after I changed the oil, and fully functional.
Am I obsessing?
I know all gears get hot, but the whine caught me off guard, and the temp was more than I expected yesterday after a highway drive with no racing....that happend later last night:gears:
Must admit I was a touch lax on doing the second oil change, but not past rec from Kurt. The whine was minimal, but as my friendly service manager knows, I hear EVERY change in my cars, no matter how small. Do I need Prozac or what?

Dbluegoat
01-29-2006, 07:13 PM
I have never felt mine

GMH GTO
01-29-2006, 07:22 PM
You put in transX for your LSD additive???

During gear break in, work hardening of the gears cause the fluid temp to go abnormally high. This can prematurely burn the gear if lubricant breaks down due to heat.

For the first 500 so miles I changed the gear lube 4 times. Once after 100 miles of figures 8s. ran straight 80W90 gear oil. Ran some Torco RGO 80W90 with Torco type F only 2oz. FM. another week I changed to Kaaz gear oil, went to the track. Noticed some gear whine, changed to Torco RGO 85W140 and Torco Type F FM, ran great since:)

Nmbr1GMfan
01-29-2006, 07:37 PM
I have never felt mine
I touch mine with relative concistency.:gr_devil: I'll be here all week :gr_jest: . No seriously, Bill they do get hot, after a trip for me to Brandon, I checked it and could barely touch it. As for the gear whine, a slight bit I would consider normal. If you hear it over the radio I would check it. TODD

Baaa
01-29-2006, 08:04 PM
135-140 degs f is all the human skin can touch for more then 1-2 seconds. That temp is just fine for the diff. I have checked mine with my IR camera and thats exactly where it runs after a nice hard drive.

Swampgoat
01-29-2006, 09:21 PM
Thanks guys...
I just went and did 30 miles at 60-75 with pulls up to 120, and pulled the fill plug and got 135 on a mechanical oil temp probe I carried with me when I left the Navy. Ambient here is 72. My mind is at a better place now. I was thinking about it while I drove and realized my hot water heater on house is at 140, and I sure as hell can't touch that for long.
The minimal whine was gone. I actually heard something because I had my windows up and the radio off, and noticed it. Certainly never loud enough to hear over radio, wind noise or exhaust if windows down.
Cool .
I used 80/90 with no FM initiall, then Kaaz, then went to 85/140 Valvoline High performance about 700 miles ago. I used CRC modifier when I went to 85/140. They sell it under the name trans X but it is specifically for LSD units, not trans.
Couldn't find Torco at 3 different parts stores. Will search more and seek advice from local speed shop on best available here.
Thanks

DiffTechnics
01-29-2006, 09:50 PM
Thanks guys...
I just went and did 30 miles at 60-75 with pulls up to 120, and pulled the fill plug and got 135 on a mechanical oil temp probe I carried with me when I left the Navy. Ambient here is 72. My mind is at a better place now. I was thinking about it while I drove and realized my hot water heater on house is at 140, and I sure as hell can't touch that for long.
The minimal whine was gone. I actually heard something because I had my windows up and the radio off, and noticed it. Certainly never loud enough to hear over radio, wind noise or exhaust if windows down.
Cool .
I used 80/90 with no FM initiall, then Kaaz, then went to 85/140 Valvoline High performance about 700 miles ago. I used CRC modifier when I went to 85/140. They sell it under the name trans X but it is specifically for LSD units, not trans.
Couldn't find Torco at 3 different parts stores. Will search more and seek advice from local speed shop on best available here.
Thanks


Bill

I believe you can buy the Torco Direct from them I believe !

Kurt

Speedy0009
01-29-2006, 11:23 PM
This is where I ordered my Torco 85/140 and Type F Modifier. Took just a few days from CA to MA. Put in in a few weeks ago and the rear is silent and smooth, thanks again for that one Kurt and Anthony!

http://www.torcoracingoils.com/products/product_list.asp?intProductsClassIDPK=9&intProductsTypeIDPK=11&intCurrentMarket=9

GMH GTO
01-30-2006, 12:55 AM
www.torcousa.com

Remember Torco RGO is what you want.

Don't wanna use synthetic gear oil with Kaaz.

Swampgoat
01-30-2006, 01:50 PM
Thanks again guys....got an order of the good stuff coming. I knew not to use synth, but didn't go mental on the FM as it is still on accelerated oil change schedule.
New rule: only the best for my pumpkin!!

LiqTenExp
01-30-2006, 02:54 PM
they only have 85 weight there not 75. How big of a deal is this?.

Swampgoat
01-30-2006, 08:26 PM
In Florida heat and psycho driving, I'll take the extra thick, thank you!!