Checked the How to Threads (immensely helpful) but I needed to clarify a few things.

1. Going to use 75w/140 gear oil for the axels and diff (all I can get here in Germany). I know the RAVE calls for 75w/90 but the consensus is that it's not an issue. Does it matter that I live in a much colder climate?

2. Going from mineral engine oil to synthetic...anything need to be done? Going with Royal Purple on all my oils and bottle says, "no special procedures" need to be done?

3. Doing the tranny service with filter and was going to go with Royal Purple synthetic AT fluid. Don't know of anyplace that can do the tranny flush. What is the damage of putting in the 6-8 quarts of synthetic on top of the old stuff. I know, I know just kick me in the ***** on this one.

4. Can't get Dexcool here so....Preston 50/50 it is. What are your thoughts on that. Mind you I going to do the antifreeze/coolant flush.

5. Was only able to get my hands on 1 bottle of seafoam (a guy from work had a bottle kicking around). Is it enough to do half in the intake and the other half in the engine (the actual seafoam website has this as the norm).

Thanks in advance for the information.

 

1) It is fine.
2) Just watch for consumption for the first oil change interval
3) Read the sticky, drain and refill at least twice.
4) That is fine as is G12 or G05 or green for that matter just flush first with water.
5) Don't bother with seafoam in the gas (its a poor cleaner that way) use the whole can through the plenum. Use techron or anything else with PEA for in the gas tank.

 

How many miles on your truck?
I wouldn't do a flush, just to add 12 quarts of Royal Purple, if you are over 80,000 miles cause backing flushing a tranny can be hard on them and only putting 5 quarts of Royal Purple won't benefit you.

 

Thanks for the replies. I'll press ahead with the transmission service without switching to synthetic. The truck has 72k on it and I don't feel like pressing my luck with having to replace a tranny.

One last question, how much gear oil do the front and rear diffs take? Thanks in advance.

 

Diffs: 3.4pt per diff for refill, and 3.6pt from dry
Transfer box: 4.1pt refill, 4.8 from dry

 

1.8 quarts each and 2.2 for the t/case, all using the same oil.

 

You will be fine switching to synthetic, most of us use valvoline maxlife which is synthetic. Dex/Merc ATFs should be compatible. When you do a drain and refill you usually get a bit over 5 quart in (about half the capacity of the transmission). So if you do 1 drain and refill you have 50% new fluid and if you do it a second time you get 75% new fluid then 88% then 94% then then 97% so there is diminishing returns after 2 drains.

 

Thanks for all the inputs. Just spent 140 bucks on gear oil...wow. Guess you get what you pay for...at least that's what I hope.