Mix Synthetic Differential Lube brands?????

rv_safetyman · September 18, 2011, 09:39:56 AM

We are on the road and I have a small "leak" in my differential area. Tried to fix it before we left, but still have a small loss.

When I had to rebuild the diff and dropbox, I filled it with Shell Spirax S (I think it now has an additional letter or two after the "S" designation) fluid (also use it in the service truck that we tow). I thought I brought some with me, but I guess I left the bottles at home.

Now I am trying to find it on the road (currently in SW Iowa) and it is not readily available from what I can see. I am doing a bunch of searching for on-line sources, but they are not jumping out at me.

So, my question is, can you mix GL5 synthetic lubricants? One source mentions that an equivalent is Mobilelube SHC.

I will be checking on Shell Distributors in the area, but my hopes are not high.

Jim

Lin · September 18, 2011, 10:03:40 AM

You could try to call Shell tech support (713 237-8645, option 4 then option1), or the manufacturer of the replacement oil. Generally, when I have inquired about such things, they say something to the effect that if they meet the same standard, they are compatible. Although I am not positive they are right, I do not think I have had noticeable problems on the rare occasion I have mixed brands. Of course, that does not mean that there were no invisible issues.

luvrbus · September 18, 2011, 11:08:41 AM

If all else fails pour the Lucas to it Lucas will mix with everything but water

good luck

bevans6 · September 18, 2011, 11:28:25 AM

I mix brands all the time. No problems at all.

Brian

eagle19952 · September 18, 2011, 08:12:53 PM

add what clifford said or use a Chevron product,they sell more syn base stocks and additive packages than any other producer.
I believe Mobil is their only major competitor.

GMC5303Wonder · September 19, 2011, 06:03:56 AM

As long as it meets or exceeds the specs (2 letter code) of ur needs the brands mix with absoutely no problem. Just make sure you use the same weight...... you can even use a partial synthetic or a "blend" in a pinch but just remember you'll lose the benefit of having full synthetic lubricant

Ed Hackenbruch · September 19, 2011, 07:12:34 AM

The Lucas may even seal your leak.

Bill in KS · September 19, 2011, 11:08:44 AM

Just food for thought............... not all Synthetics are made from the same base stock so their compatabilty can be good or bad with other products. Some Synthetics are made from veggie oil and are ester base ( not very compatable) but cheaper to produce and the major companies sure charge a lot of $$ for the product on the shelf.
The less people know and the more they believe what they are marketed on TV the better for the major oil companies.

I'll end on this: Which do you buy more of , gas or oil and grease

Certain oil base stocks are a byproduct of making gas and needs to be disposed of, guess what we are sold as " good " motor oil .......... yep , their left overs. Majors are in the gas business and do a great job of selling use their waste at a premium price with a fancy label.

Knowledge is power
,

rv_safetyman · September 25, 2011, 10:12:29 AM

Update: I was able to find a Shell distributor that had branches in Omaha and Des Moines. They were very friendly and helpful. They transferred a case to Des Moines and one of the family members picked it up for me when they were there for a class.

Yesterday I crawled under the bus and checked the fluid level. It started out about 1/4 inch down when we left and took about 1/2 quart to top off. Not as bad as I had feared.

The leak first appeared to be the drain plug (had some damage). I replaced it and now the leak seems to be between the rear end pumpkin and the housing. I have tightened all the bolts again and still have some seepage. Not sure what to do next, but I am good to go for this trip.

I might try to find some Lucas rear end fluid and see if it says anything about "sealing".

Jim

luvrbus · September 25, 2011, 10:51:20 AM

Jim, it will help on a seal not the differential probably someone used silicone on the gasket when mating the 2 I never use that crap on a gasket or would never use it mating the 2 without a gasket either like some I have seen

good luck

GMC5303Wonder · October 05, 2011, 02:45:41 AM

If it is silicone and you don't have a gasket available..... use a gasket maker called the right stuff. Sold at all auto parts stores. On newer vehicles this actually is the gasket used in many applications and is the best sealing silicone/gasket maker out there.

luvrbus · October 05, 2011, 04:12:50 AM

If you use a gasket maker use the CAT brand I do carry that along with their liquid o-ring maker

good luck

Just A Newell · October 05, 2011, 05:34:34 AM

Have not used the cat brand, but the right stuff is the goto product around the farm.

bevans6 · October 05, 2011, 06:18:01 AM

I use the silicone products on stuff that I don't care if it leaks a bit and that I plan to take apart a lot. Like racecar gearboxes, we sometimes have to change gears at the track. I use "the right stuff" for goo if I need it since it's on the shelf most places, but have gone to the Permatex aviation sealant as a gasket dressing. One little bottle did my 8V-71 project and there is still a little left. http://www.permatex.com/products/automotive/automotive_gasketing/gasket_sealants/auto_Permatex_Aviation_Form-A-Gasket_No_3_Sealant_a.htm

Brian

Busted Knuckle · October 05, 2011, 07:09:56 AM

Jim,
Lucus is a handy thing to carry !
It can be used in the rear end, engine and wheel hubs on the road! We keep a gallon of it on the buses for emergencies! (one note it is thicker and slower pouring than molasses!)

My uncle once got some on him while using it and claims "it's the
slickest sticky stuff on earth!"

Now about that leak @ the differential. There is this shop down in Chattanooga that has plenty of experience with stuff like that! Should I look up the address & # for you?

BK

(actually I don't have to look them up as they are in my permanent memory, phone and gps! LOL)