• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

Thicker oil I can run in my 1996 4.0 OHV


sebastian323

Member
Joined
Aug 2, 2021
Messages
108
Reaction score
24
Points
18
Location
Merced, CA, USA
Vehicle Year
1996
Make / Model
Ranger XLT
Engine Type
4.0 V6
Transmission
Manual
2WD / 4WD
4WD
I am currently running 10-40 in my 1996 4.0 OHV. I am wondering what is a good thick oil I can run for engine longevity. I rarely use my truck and when I do use it is to go to the junkyard to pickup parts about 2 miles from my home or to rip around on dirt roads, so I do not care about fuel economy. Would 10w-40 be a good choice of oil ? I live in Central California, and we get a few days a year below freezing where i would have to cold start at around 28 degrees F.
 


Angie

Well-Known Member
V8 Engine Swap
Joined
May 18, 2008
Messages
1,510
Reaction score
368
Points
83
Location
Vancouver area BC Canada
Vehicle Year
92 & 83 project
Make / Model
Ford
Engine Type
V8
Engine Size
4.0L 302
Transmission
Automatic

rubydist

Well-Known Member
TRS Forum Moderator
Joined
Dec 16, 2016
Messages
985
Reaction score
835
Points
93
Location
Denver
Vehicle Year
2009
Make / Model
Ford Ranger FX4
Engine Type
4.0 V6
Transmission
Automatic
2WD / 4WD
4WD
I would not put anything thicker than 10W40 in that engine. There is no reason to do so.
 

Blmpkn

Toilet enthusiast
Supporting Member
Joined
Feb 15, 2020
Messages
5,497
Reaction score
6,350
Points
113
Location
Southern maine
Vehicle Year
2023
Make / Model
Ford Bronco
Engine Type
2.3 EcoBoost
Engine Size
2.3
Transmission
Automatic
2WD / 4WD
4WD
Total Lift
2.5"
Tire Size
285/75/18
My credo
Its probably better to be self deprecating than self defecating.
The best oil for longevity is whatever the manufacturer reccomends.
 

19Walt93

Well-Known Member
Ford Technician
V8 Engine Swap
Joined
Nov 13, 2018
Messages
4,475
Reaction score
4,412
Points
113
Location
Canaan,NH
Vehicle Year
1993
Make / Model
Ford Ranger
Engine Type
V8
Engine Size
351
Transmission
Automatic
2WD / 4WD
2WD
Total Drop
3"
Tire Size
235/55R16
My credo
If you don't have time to do it right will you have time to do it over?
I wouldn't use 10w40, the formula hasn't ben updated for a long time and thicker oil causes more drag from the oil pump. I'd use 5w30 in it, just like I do in the 351 in my Ranger. Multi Viscosity oil isn't "multi", the viscosity is more stable with temperature changes. 5w30 for example, gets no thicker when cold than a 5 weight oil and no thinner when hot than a 30 weight. 5 weight circulates faster on startup and reduces wear. Make sure to change it at least twice a year.
 

sgtsandman

Aircraft Fuel Tank Diver
TRS Forum Moderator
U.S. Military - Active
TRS 20th Anniversary
TRS Event Participant
Ham Radio Operator
GMRS Radio License
Joined
Mar 11, 2017
Messages
12,695
Reaction score
12,388
Points
113
Location
Aliquippa, PA
Vehicle Year
2011/2019
Make / Model
Ranger XLT/FX4
Engine Size
4.0 SOHC/2.3 Ecoboost
2WD / 4WD
4WD
Total Lift
Pre-2008 lift/Stock
Tire Size
31X10.5R15/265/65R17
I would stick with whatever was originally recommended for the engine. Too thick of an oil can cause oil starvation issues when the engine is cold and cause more damage than whatever is recommended for the engine. Only in special applications would you go heavier, like racing as an example.
 

rhekman

Member
Joined
Aug 6, 2011
Messages
74
Reaction score
35
Points
18
Location
Lakes Country, Minnesota, USA
Vehicle Year
1995
Make / Model
Ford
Engine Type
4.0 V6
Engine Size
4.0
Transmission
Manual
2WD / 4WD
4WD
Total Lift
2"
I am currently running 10-40 in my 1996 4.0 OHV. I am wondering what is a good thick oil I can run for engine longevity. I rarely use my truck and when I do use it is to go to the junkyard to pickup parts about 2 miles from my home or to rip around on dirt roads, so I do not care about fuel economy. Would 10w-40 be a good choice of oil ? I live in Central California, and we get a few days a year below freezing where i would have to cold start at around 28 degrees F.
Opinions about oil on the internet are so numerous to the point of absurdity. For the most part, oil is oil - keep it clean, keep it full - and you'll be fine.

That being said, unless you're towing or racing and revving your motor to the moon out in a hot desert, a high viscosity oil in a 4.0 OHV isn't adding any more "protection". As long as you have proper oil level and pressure, the factory 5W-30 or 10W-30 will keep everything happy. If you live on a farm and have bulk 10W-40 that you use for everything else, it's not the end of the world to use in your truck too. Keep in mind though, oil viscosity isn't just about bearings, and thicker isn't always better. A thinner detergent motor oil works better in the 4.0 to flow through the tiny hydraulic lifter passages, and to keep piston oil rings clean.

This is just an anecdote (and I am not a lubricity engineer), but when I recently tore down my '95 OHV with 300,000 miles, I had the following observations.
1. Cam and main bearings were within tolerance, with no scoring or heat damage (if you would have told me 30k of wear instead of 300k, I'd believe you).
2. Rod bearings were only slightly blemised, and slightly out of tolerance.
3. Internal block and head surfaces were all clean and relatively varnish free, with a small amount of sludge in the bottom of the pan.
4. ALL (every single one) of the hydraulic lifters were siezed internally. They floated smoothly in their bores, but the internal plungers were plugged with rusty-varnishy sludge.
5. ALL the pushrods had 1/8-3/16" flat spots on the tips
6. Most of the rocker arms had flat spots at the valve tip.
7. Most of the pistons had stuck oil control rings, and plugged oil drainback passages.

If you never use the truck in freezing temperatures, then just use a name brand, high detergent, conventional (or blend) 10W-30 with an API S tag.
Change oil and filter every 3000-4000 miles. Also replace the PCV valve every couple of years.
 

gw33gp

Well-Known Member
U.S. Military - Veteran
TRS Banner 2010-2011
Ham Radio Operator
Joined
Aug 7, 2007
Messages
1,727
Reaction score
530
Points
113
Location
Costa Mesa, CA
Vehicle Year
2002
Make / Model
Ford
Engine Type
4.0 V6
Engine Size
4.0 SOHC
Transmission
Manual
2WD / 4WD
4WD
Tire Size
33"
Pretty much everything said in this thread is true. However, I can tell you I ran my 89 STX with a 2.9L engine for almost 200K miles using Valvoline 20W-50 synthetic oil. When I sold it to a co-worker, it still ran like new and used no more oil than it did when new. The reason I ran the higher viscosity oil was; I live in SoCal and towed my race car all over the country and much of that was across very hot desert and climbing mountains. It also did a lot of duty off-road. I worked that engine very hard and ran it at fairly high rpm to keep it in the power band.

The only times I could tell the oil viscosity was too high was when I went to the mountains to ski. Then it was only noticeable if I stayed overnight when it was very cold. The engine would crank over slow in the morning, but would always start and apparently caused no damage. My co-worker that bought it drove it at least another 100K miles with no engine problems.

I ran 5W-30 and 10W-30 Valvoline synthetic oil in my 02 Ranger with the 4.0 SOHC engine from new until I got to around 230K miles. It started getting a blinking oil pressure light at idle after a long run on an Interstate, especially when towing. I began running 10W-40 then. That helped a lot. I run a micron bypass filter and that takes about 15% of the oil flow which is not a problem until the bearings get some wear. I eventually installed a higher volume Melling oil pump and now run 5W-40 oil and have no problem what so ever with oil pressure.

For your situation, I don't think you need a higher viscosity oil. Use what Ford recommends for your engine. I think the 10W-40 would work OK too if that is what you like, but I doubt you are going to get any longer life out of the engine. I found 10W-40 Valvoline full synthetic oil was getting difficult to find. It seems other brands and conventional oil is still available in that grade though.
 

ekrampitzjr

Well-Known Member
Joined
May 28, 2021
Messages
754
Reaction score
1,039
Points
93
Location
Virginia
Vehicle Year
2011
Make / Model
Ford Ranger
Engine Type
4.0 V6
Transmission
Automatic
2WD / 4WD
2WD
In years past I tried thicker oil in various high-mileage vehicles that had oil consumption and other problems from age and miles. At best the difference was marginal. I learned and I wouldn't do it again.

On my stepfather's 1972 F-100 with a 390 FE, thicker stuff caused the oil pressure gauge to read lower than normal even at highway speeds, which was worrisome. Clearly the oil pickup and pump weren't too happy with higher viscosity, despite the wear on the engine. But that truck was in a race between engine failure, transmission failure, major electrical failure, and body failure from rust, and instead of seeing which one was going to win, we eventually scrapped the truck. (The original owner had hauled fertilizer for his farm in it, and corrosion from that stuff soaking into the metal affected everything.)

If you really think the engine "needs" 10W-40 or, goodness forbid, 20W-50, it's time for a rebuild.
 

SenorNoob

Well-Known Member
TRS Event Participant
Joined
Oct 24, 2012
Messages
2,348
Reaction score
520
Points
113
Location
Middle Tennessee
Vehicle Year
1988
Make / Model
Ford
Engine Type
4.0 V6
Engine Size
4.0
Transmission
Manual
2WD / 4WD
4WD
Total Lift
1.5" Front + 4" Rear
Tire Size
245-70-R16
I tried 10w-30 in my 93 4.0 and it was ok when warm, but the first below freezing day the pump just wouldn't. Zero oil pressure. Had to get another ride to work and change it the next day. (Still below freezing. Took an hour to drain.)
 

holyford86

Some guy with a problem
Supporting Member
Article Contributor
RBV's on Boost
GMRS Radio License
Joined
Aug 6, 2007
Messages
2,208
Reaction score
575
Points
113
Age
37
Location
Plattsburgh, NY
Vehicle Year
many
Make / Model
Ford
Engine Size
4.0
Transmission
Manual
2WD / 4WD
4WD
Total Lift
7
Tire Size
33x12.50R15
I've been running Shell Rotella T6 5w40 in mine for quite some time. much better cold weather performance than 10w40 and has good oil pressure when hot as well. I change it every 6k miles.
 

cbxer55

Well-Known Member
Joined
Oct 9, 2009
Messages
1,863
Reaction score
763
Points
113
Location
Midwest City, Oklahoma
Vehicle Year
1998
Make / Model
Ford
Engine Size
3.0
Transmission
Automatic
Another oil thread. Yeah! WINNING!

I've run nothing but Valvoline Maxlife 20w-50 in my 98 3.0 Ranger for 22 years. Never had a problem. I've run Mobil One 10w-40 in my 04 LIGHTNING 14 years, no problems. I run 10w-40 Mobil One in my 2007 4.0 Mustang. No problems. I run 15w-50 in both my Suzuki Motorcycles, one for 16 years. No problems.
 

Sponsored Ad


Sponsored Ad

Staff online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Kirby N.
March Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top