A friend of mine is convinced 6spd kill motors. he says that lugging them in 6th gear on the highway beats the bearings to death which in turn causes low oil pressure and eventual engine failure. i am not as believing so i need your information to prove him wrong... ok its no so much i dont believe what he is telling me its more of a matter of getting down to the bottom of this so EVERYONE knows! btw auto guys are welcome to answer too

1. how many miles do you have on your motor?

2. what is your oil pressure at idle and on the highway traveling 70 mph in 6th gear?.. its around 1600-1700 rpm but your tach probably reads 1900.

3. do you use synthetic or conventional oil and what weight?

*remember your values are only relevent after the car has been running for a good 20-30 minutes so the oil is HOT*
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1. 85k

2. mine carries about 20 psi at idle and 38 or so on the highway

3. i use regular valvoline 10w30

 

1) 383 has 15k, my old motor lasted 150,000 with the M6 until it spun a rod bearing.

2) 'bout 30 idle and 35-40 cruising

3) using reg. penzoil 10W-40

 

111k on motor
about 60psi I believe when the motor is runnin' above idle
Mobil 1 Synthetic 5w-30

 

well, when the motor actually ran.... 87k miles

around 30-40 psi.

valvoline 10w40

 

79 thousand miles
around 15 at idle
and crusing in is really low around 20-30

 

60k

about 25 at Idle, about 41 cruising.

oil, I forgot, I know it's the good stuff, just to tired to look.

 

Brad - I don't know if its the low oil pressure, or the knock/detonation that the 6th gear causes. I rarely use 6th gear (unless I'm over 75mph). The gas mileage isn't noticeably worse, and I feel safer.

3.42s and the 6th gear are not optimal IMO. Maybe 3.73:1 or 4.10:1 gears. A larger cam doesn't like to be lugged at 1500rpm in 6th.

Ryan

 

I have 89K miles and use 5W 30 oil. About 20 at idle, after 1500rpms and above its at 38-40.

Aaron

 

Dont know what the pressue is EXACTLY but its the same place on the gauge as when it was new, now has 165,000 miles on it. Pennzoil 10w40. Cruising RPMs at 70 are about 2100 with the 4.10s.
Ron

 

88,000 miles
idle about 15-20 psi
at speed 40 - 50 psi
Mobil 1 5w30

 

150,000 miles and have always used Mobil 1 5w30

18 psi at 1,000 RPM
34 psi at 2,000 RPM
45 psi at 4,000 RPM

Pressures obtained using a mechanical gauge (not the dash gauge) so they should be accurate.

Intersting theory, don't neccessarily believe it, but still interesting...

 

1: 67,000
2: at idle - 30 psi - at highway speeds - 40-60psi
3. Mobil 1 10-30 synthetic

 

103,000 miles
at idle maybe 20psi (according to the new oil pressure sending unit which I think is reading different from the one I broke)
high way speeds at 70-80mph cruising at 1800-2000rpms 40psi-50psi
I use 15w 50 mobile one.
85%% of the miles on my car is highway miles.
other 15% are very hard driven miles.
no metal shavings in the oil at all.

 

If you are in 6th gear, and your under 1000 rpms and it is chugging, you should not be in 6th gear. I can't see how anyone can say 6th gear will cause problems engine wise. Working at the dealer since tese cars first came out (4th gen), I have never seen any problem like mentioned from 6 speed cars.

 

76k miles

30psi at idle and 45-50psi at 1900rpm

I run 10w30 Mobile 1 in the summer (5w30 in winter) and just switched to a PureOne oil filter and noticed my oil pressure dropped a bit.