Amsoil 75-90 Initial Report (better fuel mileage??)

[Shelby Griggs]

Last weekend I changed the rear differential fluid, replacing with Amsoil 75-90. It is possible that the marketing claim of 4. 83% better mileage is true. I don't usually put much stock into those types of advertising. Coincidence or not, I just fueled up and I have a new mileage record for my truck. 18. 9 MPG, whereas my previous high was 18. 1 on one or two occasions only, with 13K to date on the truck.

This tank of fuel was not on what I call an economy run. I kept close to the speed limit (55-65), but I started at about 3500 feet, went over a 5000 foot plus pass and down to around 1000 feet. I then repeated this route in reverse. I did this two days in a row, about 500 miles total. On each of the return trips, you have an essentially uphill leg for around 30 miles while gaining the 4000 feet plus of elevation. It amazes me at the economy even running in the mountains. I am attributing the increased mileage to the synthetic gear lube. Maybe jumping to conclusions, but nothing else changed. That $45 of oil, plus my Saturday afternoon will pay for itself shortly, if that was really the reason for the almost 1 mile per gallon increase in economy.

BTW, I have a custom work bed on the truck that does push more air than stock and I weigh about 8300 pounds.

I am in no way affiliated with Amsoil, don't even know any Amsoil dealers. You can buy the stuff right off of the shelf at GI Joes (a chain of automotive and sporting goods store here in the NW. )

Shelby

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2001. 5 2500 QC LB 4WD, ETH (Built 09-10-00), DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 12310 miles as of 05-01-01. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

 

[Randy J]

Shelby,

I can second what your reporting. I changed my truck over to full synthetics a little at a time. The last thing to change over was the front & rear differential, and the transfer case. After changing it, at 60,000 miles, my milage went up about 1. 5 mpg average. My average is now right at 19. I've even hit a high (all highway driving of course) of 21. The synthetics definately helped.

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Randy Jones, San Antonio, TX, rdj@gvtc.com, 98 1/2 QC, 4X4, American Racing BAJA's, 285/75/16, Amsoil throughout, Superstar 3000 export radio, Firestik antenna with fender mount, Fire-ring cable, Mag-Hytec Deep transmission pan

2000 VW Jetta TDI, auto, 45 mpg average

 

[Cobra]

Shelby

I am not quite ready to change my diff, but when I do I would like to go to Amsoil syn. But, did you happen to rear the post about a week ago, a guy had rear end problems and thought it might be from the synthetic leaking past the seals. No one is sure about that, just thinking. I would be interrested to hear from you after about 10k miles. Good luck, happy for your increase in milege.


01. 5 RAM 2500 QCISB 4x4 5 spd 3. 54 LSD,Camper pkg,Tow pkg,Westin nerf bars,jacobs E brake, Patriot blue/siler

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Bill Kute

 

[lschultz]

I have around 34000 on mine. Everything but my front diff. (have not got around to it)is on Amsoil. Mileage is running high 20 to 21 now.

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2000 Dodge 4x4 Quad Cab SWB 5-SP
2001 VW NB TDI
AMSOIL(#504865) DEALER & USER

 

[DocStressor]

I HATE the way Amsoil is marketed and I am still not convinced that Amsoil products are really any better than other reputable synthetics. Having said that, I also seem to have picked up about 1 mpg empty and 0. 5 mpg hauling the camper since switching to the 2000 series 75W-90. This is compared to the 90W conventional stuff that I used to change every 5K. Now that I no longer drive through water, I will keep the Amsoil in there until oil analysis tells me to change.

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1999 Quad cab 2500, SB, SLT, 4X4, 5-speed, 3. 54, tow and camper package, Lance 820 camper, Lance cabover stabilizers, Rancho 9000s, Airlift airbags,Reese Titan V hitch, Mag-Hytec differential cover with Amsoil 2000 75W-90 lube, Amsoil air filter

 

[LSMITH]

My switch was not to Amsoil, but to another quality synthetic. I also noticed 1-1. 5 MPG improvement. I know it was the oil, because nothing else has changed and the driving I do is the same every day.

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99 2500 QC 4X4 AUTO SB 24V LARAMIE SLT 3. 5 LSD 285-75-16'S SPA Boost/EGT Rancho 9000's Everything but leather NRA Member Great Lakes TDR Member

 

[Shelby Griggs]

Thanks for the feedback guys.

Lee Weber,

Not necessarily a fan of the type of advertising that Amsoil does either, usually pretty skeptical about these things, but if it provides better mileage, I won't complain.

Bill Kute,

I saw that thread. I will definitely post any information that I think is oil related as far as seals, etc. Personally, I agree (at this time) with most of the members who did not think the Amsoil to be the cause.

I will definitely be doing the front differential and the transfer case with synthetic in the near future too. I am sticking with the Texaco MTX for the 6 speed though. Too soon for the engine IMO.

Shelby

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2001. 5 2500 QC LB 4WD, ETH (Built 09-10-00), DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 12310 miles as of 05-01-01. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

[This message has been edited by Surveyor Shelby (edited 05-19-2001). ]

 

[Cobra]

Lee Weber

Are you saying that you change the Differential every 5000 miles?

Also are you guys using after market diff covers with the drain valves?

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Bill Kute

 

[Sled Puller]

I find it amusing that it only takes ONE post from someone who is misinformed, grasping at straws, or just skeptical, that thinks a synthetic caused a leak among thousands of posts saying it doesn't, is all it takes to put the seeds of doubt into the masses!!!!!
We the sheeple! LOL #ad


BTW, that guy with a leak, I believe it was a poor install of the seaL FROM THE DEALER.

I wonder if the masses will blame their problems on the wanna-be synthetics at Wal-Mart?

Gene


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CPFF's Dowell Pin Jig Available in GLTDR Region! 1997 Cummins Dodge 4x4 "One Piece At A Time" Bombed & Amsoiled, NO LEAKS!! Amsoil Executive Direct Jobber, Member of: NRA Business Alliance, GLTDR, WANTED: Wrecked Dodges.
www.awdist.com

[This message has been edited by MGM (edited 05-20-2001). ]

 

[TwoSlick]

If you are changing over from a 85w-140 petroleum gear lube to a 75w-90 synthetic, you will definitely see a small (3%-5%) increase in fuel efficiency - particularly in very cold weather. The comparison Amsoil cites on their container was from just such a test in OTR trucks, running on the highway. I would not expect much of a difference if you already have a 75w-90 in the rear axle, especially if it's a synthetic of some type.

TooSlick

 

[DocStressor]

Bill-- Yes, I used to change every 5K, but that was due to a special application. The truck was used for field work where I frequently had to drive through streams that cut across gravel roads. I was worried about water entering the differential through the axle tubes. So I used cheap 90W lube and changed it often. Since the truck is no longer used for submarine duty, I now use synthetic for normal service. The drought seems to have returned to the West, so this would no longer be an issue anyway.

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1999 Quad cab 2500, SB, SLT, 4X4, 5-speed, 3. 54, tow and camper package, Lance 820 camper, Lance cabover stabilizers, Rancho 9000s, Airlift airbags,Reese Titan V hitch, Mag-Hytec differential cover with Amsoil 2000 75W-90 lube, Amsoil air filter

 

[HC]

Hash, rehash, but I gotta ask:
I'm using the Amsoil 75w(?)-140 in the rear, 'cause I still feel a little more comfy with that than with the 75W-90.
I already know that others have towed with the 75W-90 with good results, but, does anyone have oil analysis results to prove the 75W-90 is equal in protection, or, if not equal, to at least put a number to it?

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2001 ETH, QC, LWB, 4WD, 3. 54, SPA Pyro & Boost, K&N RE-880 w/foam pre-cleaner, ARE Z-series Cab-high shell, Rear ARB locker, and all kinds of synthetic fluids...

 

[TwoSlick]

HC,

If you put on the MagnaTec cover and increase the fluid capacity, I believe the 75w-90 is just fine. For heavy towing with the original cover, the 75w-140 will handle shock loads better, simply because it's more viscous. The ASTM, Four Ball Wear Scars on these two oils are comparable; measured at the same temp - this test is primarily of the anti-wear additive package.

TooSlick

 

[JJW_ND]

I have ran the Series 75W90 the last few changes. I pulled stock trailers (doubles, and stacks of flatbeds). Have 190K on my 96. The last samples checked at 30 - 40K miles on the rear diff. oil checked better then previous samples of original Amsoil 75W90. The last sample at 151K on the truck, 35K on the oil: Iron 57ppm, visC40 100. 8, TAN 2. 76.

I have the LDS and it still is as tight as when new. Just have to repair rear pinion seal at 190K.

I believe that Amsoils 90wt vs 140wt oil could "wearout" quicker under similar use. I doudt on gets much better protection. I have not been able to wear it out in 35K miles. This is with heavy loads or very hard pulls (60' or trailers).

I would worry more about cold weather use (I do in ND). Straight 90w very bad at -20.

jjw
ND

 

[Sky]

I too went to the Amsoil 75-140, I also got it at GI Joes Shelby, 12. 00/ Quart #ad
. To be honest I really cant tell a difference. The reason being that if I would stop adding stuff to my truck for a month or two I might be able to tell whats working and how much. Also I am pulling diffent weights constantly over passes all the time so its hard to get a true MPG reading. I do know it isnt causeing any harm!

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2001 QuadCab,SWB,Auto, 4X4,4" Flowmaster Raceing Exhaust, DTT TC & VB, EZ Box, Bosch 275 Injectors, Mag-Hytech transmission pan/Dana 70, K&N, 33" BFG AT'S... ... .....

 

[Cobra]

Hey guys,
I'm sorry if I sound stupid but I have to ask so that I don't mess up my truck. If I change to AMSOIL do I have to put an additive in for the LSD, and is it alright to use the stock diff cover. I use the truck to haul a Coachman Ranger slide-in. Slide-in weighs in at 3200 pounds not counting clothes,food, and water. Truck will gross about 10,600.

01. 5 RAM 2500 4x4 QC, 3. 54 LSD,Patriot blue/silver

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Bill Kute

 

[Cobra]

Hey guys,
I'm sorry if I sound stupid but I have to ask so that I don't mess up my truck. If I change to AMSOIL do I have to put an additive in for the LSD, and is it alright to use the stock diff cover. I use the truck to haul a Coachman Ranger slide-in. Slide-in weighs in at 3200 pounds not counting clothes,food, and water. Truck will gross about 10,600.

01. 5 RAM 2500 4x4 QC, 3. 54 LSD,Patriot blue/silver Rear air bags, Jacobs E-brake
Westin CPS step bars

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Bill Kute

 

[LSMITH]

Bill, I can tell you for sure that you can use the factory cover with any oil, regardless of brand, synthetics are fine with the OEM cover. I do not use Amsoil personally, but the common concensus seems to be that the Series 2000 does not need a limited slip additive. One of the Amsoil guys is sure to pipe up soon and give you a definite answer on aditives.

 

[fest3er]

Originally posted by LSMITH:
... the common concensus seems to be that the Series 2000 does not need a limited slip additive. One of the Amsoil guys is sure to pipe up soon and give you a definite answer on aditives.

I'll bite! Officially, you may may need to add the modifier to the diff.  When I put Amsoil in the rear, I decided to hold off on the additive until I could determine whether or not it was needed. As it turns out, the rear wheels haven't hopped going around corners, so I haven't put any in. I would suggest you do the same: wait and see if you need it. You probably won't, but YMMV.

Fest3er

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Neal P. Murphy; Amsoil dealer
'98 auto, 4X4, valve- and BOMB-challenged; Yokohama 225/75-19. 5 on Rickson wheels; 67K miles; Amsoil dual remote filter

 

[RBrush]

I've been useing Amsoil in everything I've owned since 1978 with good results. I too was buying it at G I Joes, but discovered I could by it on line and sign up as a prefered customer ($20 a year) and save some wherewithall. Check it out. However all the prices you see on line are the retail prices. For example, the listed price for the BMK15 Dual Remote Filter set up is $227. 00 and I paid $176. 50. Hope this helps out it the $ department.
Rich

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96 regular cab, driftwood,5speed,3. 54's, weld wheels, window tint,amsoil,Dual remote bypass, preluber, K&N,Horton on order. BOMBing to proceed soon.