Fluid Change

[QueensJeep]

Hello,

I am getting ready to change all the lubricants in my KJ. I know that for the Transfer case and ****** I need ATF+4. But I dont know if I should use synthetic in the front and rear differentials.

I picked up the limited slip additive for the rear diff since it is Trac Loc. Also, what weight oils do you recommend for the front and rear diffs. I do not do any towing, or severe off roading.

Is Valvoline ATF+4 ok or should I purchase Mopar fluid?

Also, what type of antifreeze is in this car? What should I buy?

Thanks!

 

[tjkj2002]

ATF+4 is ATF+4,any brand will work,Castrol makes ATF+4 also,all are full synthetic fluids hence the high cost.Most synthetic gear lubes(like Royal Purple and Amsoil) already have the frition modifier in the oil so none is needed,having sythectic gear oil is cheap and if you don't get to change the diff fluids every 12,000 miles like you are suposed to it's cheap insurance.I use 75/140,if using dyno gear oil use 75/140,synthetic you can get away with 75/90 if you don't tow,offroad,or live in a hot climate.All KJ's(all Chrysler vehicles made after '00) use GO5 coolant,Zerex makes it and is at most parts stores.GO5 does not mix with any other type of coolant,mixing GO5 with other coolants turns it into acid.

 

[QueensJeep]

Thanks, So 75/140 for both the front and rear is ok? I will def go with synthetic for a few more bucks. I just didnt want to hurt anything with the synthetic.

If I use Mobil 1 lube and the LSD additive with that cause any problems? Does Mobil 1 have the additive in it?

 

[tjkj2002]

Thanks, So 75/140 for both the front and rear is ok? I will def go with synthetic for a few more bucks. I just didnt want to hurt anything with the synthetic.

If I use Mobil 1 lube and the LSD additive with that cause any problems? Does Mobil 1 have the additive in it?

I'm not totally sure if Mobil1 has the friction modifier in it,read the labels on the bottle and it will tell you.If it does do not add any more friction modifier it can ruin your LSD.I know that Amsoil and Royal Purple have friction modifer already added,can't say forsure about Mobil1 though.

Going 75/140 F/R will not hurt anything if using synthetic since it flow better then dyno gear oil of the same weight.I use 75/140 F/R and have no problems.