Overkill in a Jeep?

[Studebaker]

After 40 years of driving, I finally own my first Jeep. The Cherokee had 70,000 miles when I bought it in September, and now has 92,000. I swapped it over to synthetic upon purchase and all is well. I am using Motorcraft FL1a filters, and have tried Havoline Synthetic, GC, and valvoline synpower. I have been changing it at less than 5000 miles. The Valvoline I have in it now, I am trying to stretch it to 6,000. The oil looks fine, its just hard to teach an old dog new tricks. My gf has an '03 Wrangler and I do dino changes at 4,000. I am considering using 5w-40 Rotella T in both and doing 5-6,000 oci's. Both have a 4.0 motor.
The 4.0 is a wonderful, reliable, but archaic motor. Is synthetic overkill for this motor. Maybe a good blend?
The 4.0

 

[Greaser]

The combination you mentioned is a good one and any vehicle that you deem to be of virtue should have the best fluids that one can afford.Being fond of Jeeps myself give them the best you can.

 

[TallPaul]

I like the idea of running synthetic in it. I am running synthetic in my wife's Aerostar which has 107,000 miles (over 100,000 when I switched to synth). FL1A is a great filter.

As long as the topic is overkill, if you want an extra long filter (1.5 inches longer than FL1A) order a Purolator L40017 from Advance Auto for $6. Fits same as FL1A.

 

[Gary Allan]

He can probabaly fit that on his Cherokee, since, IIRC, he's got a right angle mount. The Wrangler is about max'd out with an FL1A size.

I'm using RTS now in the Jeep fleet. The only thing that I've noticed is a little more drip (you don't see a spot on the ground) from the rear main seal. This doesn't occur on my 2.5 auto (SE), nor my son's 00 Cherokee (also an automatic) ..so we may have added a little crank play in 97k with the 5 speed, who knows? The 5 speed is going back to T&SUV. One other member has reported this.

RTS isn't the bargain that it once was. It was $12.8x/gal ..and M1 T&SUV was $4.77/quart (still is, by the quart). Now T&SUV is $20.00 for 5 quarts (5 quart jug)and RTS is $13.4x ..so the gap in price between a Group III and a PAO tips the scale pretty heavily in T&SUV's favor.


I would say, under just about anything other than an abusive environment, you should be able to manage 6 month OCI's for both. Even if you do up to 20k a year.

 

[Ryan00TJ]

I'm planning on using either Rotella 5W-40 Syn or M1 T@SUV 5W-40 in my 2.5L and brother's 4.0. Keep is simple and change every 6 months or 7500miles.

 

[Eddie]

My 95 GC Jeep has over 194,000 on it since new and I used Mobil 1 and PureOne oil filters.

 

[k2xj]

While its true, jeeps will run on sand and milk...i think its best to give it the best you can afford. GO JEEPS!!!

 

[MNgopher]

I used to run RTS in my '88 Cherokee with the 4.0l. I did that for well over a year, and it ran just fine on the stuff.

I switched back to a 10w30 (Currently Citgo Synthetic) for a variety of reasons, and I haven't regretted my choice yet (UOA to come soon on the first batch). Idle has smoothed out again, and I'm not getting the pressure drop I used to get on dino 10w30/5w30 oils after long hot runs on the freeway. RTS got rid of that, but the Citgo doens't do that either.

I also stopped using RTS because I got tired of making a trip to Wal Mart for it, as that was the ONLY thing I ever bought there, but thats another story.

The short story is that a decent oil will serve your Jeep just fine, and RTS should work well if you choose that route.