Need new fluids all around

Chilidawg

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Hey guys and gals. Bought a 99 TJ 2 weeks ago with 90K on the odometer. It was one family owned in Ga its entire life, driven by grandma. Well not knowing what all has been to to it I am wanting to replace all drivetrain fluids. It's stock with Dana 30 and 35 axels, and 5 speed. Looking to do both axels, transmission and transfer case. What brand and weight would you recommend for a Ga jeep that is mainly driven on road.
 

MountaineerTom

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If it has an owners manual, I’d start there and use what it calls for. As far a brands, I’ve always liked using Valvoline conventional products. I do use thier Max Life 10w-30 motor oil which I believe is a conventional/synthetic blend.

Im not knowledgeable on the manual transmissions but others here recommend specific oils for some of them. I’m sure they will chime in on it.
 
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Chilidawg

Chilidawg

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If it has an owners manual, I’d start there and use what it calls for. As far a brands, I’ve always liked using Valvoline conventional products. I do use thier Max Life 10w-30 motor oil which I believe is a conventional/synthetic blend.

Im not knowledgeable on the manual transmissions but others here recommend specific oils for some of them. I’m sure they will chime in on it.

Thanks. I just wanted to see what real people are using, and not just what the manuals say.
 

MountaineerTom

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Some years call for different fluids. For example, my ‘06 automatic calls for ATF+4 in the transmission, transfer case and power steering. I think some of the earlier years call for different stuff but I don’t recall exactly what. As far as the 42RLE auto trans, that ATF+4 is supposedly very important as far as it running properly.

I just use the Car Quest brand of ATF+4 that Advance Auto Parts sells. For the axles, I use Valvoline 85w-140 conventional in both and 4 ounces of MOPAR friction modifier in the rear axle for the clutch pack.
 
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Chilidawg

Chilidawg

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Some years call for different fluids. For example, my ‘06 automatic calls for ATF+4 in the transmission, transfer case and power steering. I think some of the earlier years call for different stuff but I don’t recall exactly what. As far as the 42RLE auto trans, that ATF+4 is supposedly very important as far as it running properly.

I just use the Car Quest brand of ATF+4 that Advance Auto Parts sells. For the axles, I use Valvoline 85w-140 conventional in both and 4 ounces of MOPAR friction modifier in the rear axle for the clutch pack.

Thanks for that info, but I'm running a 5 speed
 
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Mike Z

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Hey guys and gals. Bought a 99 TJ 2 weeks ago with 90K on the odometer. It was one family owned in Ga its entire life, driven by grandma. Well not knowing what all has been to to it I am wanting to replace all drivetrain fluids. It's stock with Dana 30 and 35 axels, and 5 speed. Looking to do both axels, transmission and transfer case. What brand and weight would you recommend for a Ga jeep that is mainly driven on road.

Congratulations on the TJ purchase. Not trying to run your life, but if you don't have maintenance history, it wouldn't hurt to include flushing the brake fluid and possibly flushing and filling the coolant.
 
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Chilidawg

Chilidawg

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Congratulations on the TJ purchase. Not trying to run your life, but if you don't have maintenance history, it wouldn't hurt to include flushing the brake fluid and possibly flushing and filling the coolant.

It was owned by an older lady and I bought it from the son. He put 17K miles on it. He told me he did a radiator flush and fill, new brakes and fluid all the wat around. Rebuilt the rear brakes. He doesn't know what if anything his mother did to it. Thanks for the input.
 

Mike Z

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It was owned by an older lady and I bought it from the son. He put 17K miles on it. He told me he did a radiator flush and fill, new brakes and fluid all the wat around. Rebuilt the rear brakes. He doesn't know what if anything his mother did to it. Thanks for the input.

No problem. Often folks overlook the cooling system and flushing the brake fluid. Update the forum from time to time on what you do to make her your own.

People all have their own preferences, but for my 97, 4.0, 5 speed, I use Redline MT-90 for the transmission.

This is copied and pasted from an older thread. The response is from @Jerry Bransford...he knows a thing or two. In the thread, he was recommending fluids for a 1997 5 speed, AX-15 transmission. Jeep ran that transmission from 1997-1999. Thought this information might assist you in deciding fluid choices.

ATF for the transfer case. ATF+4, a full synthetic, would be a good choice.

It's real hard to beat Redline MT-90 for the transmission. I personally would not use Synchromesh from GM or Pennzoil.

For the axles I'd choose a conventional GL-5 gear lube. 75W-90, 80W-90, 85W-120, 90W-140 etc. The harder the use the higher the viscosity should be. I recommend a conventional since it has been shown (surprisingly) to help the gears run cooler than they would with a synthetic. Currie's warranty requires conventional gear lubes in their axles.
 
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OldBuzzard

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I'm using Valvoline High Performance 80W-90 Gear Oil in my diffs, with added friction modifier (any brand) for the rear Limited Slip. Conventional oil is generally liked better than synthetics — and synthetics are sneaking into lots of bottles, and not always marked on the bottle, so read the manufacturers spec sheets.

The FSM recommends ATF+3 for the transfer case, but I'm going to try Mobil1 Synthetic 5W-20. Look around for various discussions on using motor oil instead of ATF.

I'm using Red Line MTL for my 2005 6-speed, but I think your 1999 5-speed needs Red Line MT-90.
 
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ejay

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Jerry Bransford

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I'm using Valvoline High Performance 80W-90 Gear Oil in my diffs, with added friction modifier (any brand) for the rear Limited Slip. Conventional oil is generally liked better than synthetics — and synthetics are sneaking into lots of bottles, and not always marked on the bottle, so read the manufacturers spec sheets.

The FSM recommends ATF+3 for the transfer case, but I'm going to try Mobil1 Synthetic 5W-20. Look around for various discussions on using motor oil instead of ATF.

I'm using Red Line MTL for my 2005 6-speed, but I think your 1999 5-speed needs Red Line MT-90.
X2 though ATF+3 was replaced by ATF+4 years ago.