I was wondering if any one could give me some pointers as to what type of fluids I shoudl be looking at. I have 74,750 on the ticker. That makes for 34K on the trans fluid and filter and an unknown mileage on the diff's and transfer case fluids. I suspect the diffs were done at the right break in mileage (hope), but I have towed pretty heavy over the last year and have some more towing comming up at the end of next month.

1) Synthetic, worth it? If so in all the mentioned locations?

2) Transfer case fluid, a quick how to and what with....

3) Rears, do they have gaskets or will RTV do the trick?

Thank's in advance for any thoughts. I want to knock all of this out at once, mainly for peace of mind.

 

Syn is it worth it? Well differing opinions on that. For me I use it everywhere I can.

Transfer case easy to do. Some remove the skid plate others dont. The fluid can and will hit the skid plate but if you have a large catch pan no problem. I remove the top fill plug first so that I am ready to catch that stream when it comes out the drain plug. It will come out fast and dont be suprised at how far out it streams. My first time I wasnt expecting it and made a bit of a mess. Drain it then put the drain plug back in and fill it up until it comes out the fill hole. In my truck it calls for auto tranny fluid. I use amsoil syn tranny fluid in mine.

Diffs rtv works fine. Just make sure and clean off all the original gasket material from the cover and the diff. I stuffed a towel in it and used a wire brush on a drill and made quick work of it. Then use the appropriate rtv. With heavy towing I would use the weight dodge recommneds for heavy towing I think it is 90w/140 and I think they call for it to be syn. Again I use amsoil series 2000.

 

Don't forget the additive if you have a limited slip rear end. Different opinions on using it, but for under $10, WHY TAKE A CHANCE. I used mobil 1 90w/140 front and rear.

 

It also depends on different brands of lube and how tight your posi is to begin with. I run regular pennzoil in mine with no additive and my posi is working great.

 

Thanks guys, I'm going to gather some of the fluids tommorow.

I hope to be able to make a Saturday morning project out of it. I'm so stressed with our home sale/purchase, lathering myself in some automotive fluids might ease the pain.

So not to sound like an idoit, but the transfer case? That's syn. gear oil too?

In other words, can I buy the Gallons of some of this?
I suppose the +4 is sold in Qt's only? How many there? There's only one option for the trans filter, right? No brand or anything I should look for?

 

As far as I know, the +4 is a dealer only option. It's no more expensive than any other tranny fluid (thank god). I think something like 12 quarts depending on how much you let drain out. I used 11 on mine. As for the tranny filter, just go to o'reilly's and get the filter from there. It usually comes with a filter and a new gasket for the tranny pan.

 

Front & Rear Axles
I've been using 80W-90 in both front and rear axles. Change it every 30K on the clock.

Transfer Case
I've been using ATF+3. Changing it every 30K as well.

Auto Trans
Well I don't have a auto in mine. But ATF+4 is a dealer only product. Just as the Syntorque I need for my manual trans. I'm not sure about the change interval for the auto trans.

At least I only have to change my trans fluid every 60K... Being its $15 bucks a quart (need 1 gallon) for the syntorque.

 

Use synthetic in the diffs 75-80w90, and use hi-temp oil resistant silicone for covers, and ATF+4 in transfer case and tranny. If you have limited slip, you will have to use an additive, unless you use a brand that has it in it, or it specifies it is safe to use with limited slips.

 

I guess I'll offer my 2 cents. I'm a firm believer in using synthetics in the driveline. The extra cost can be justified, by extending the drain interval, as internal combustion does not take place here, and contamination concerns should be less likely.

As for adding external friction modifer to a limited slip differential, I'd say try it without first, then get some if you have chatter on turns, and then only add a portion at a time, until the chatter stops. With the Dana limited slip, it's recommended to do several figure of eight turns in a parking lot after a fluid change, to get the new stuff worked into the clutch packs.

And alas, I guess I'm wondering at this point, why we even attempt to maintain these throw-away trucks, mine's sure turned into a POS lately, the money pit. (and I'm diligent on maintenance) I drive Ford PSD ambulances with more miles on the clock, where other than oil changes, preventative maintenance is neglected, the snot's beat out of 'em, and they keep on running with no problems! Go figure.

Sorry for the rant.

 

Well the ford intersmational engine(7.3 and 6ohno) are far less reliable. I used to work on them(7.3l) at an intersmational dealer, and not many made it to very long mileage like the Cummins, without bottom engine repairs, warped heads and gaskets, oil pumps, oil leaks, and of course injectors being the biggest one at $400-$500 a piece.