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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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think i should swap to synthetic??

  • Thread starter Thread starter Foxfan88
  • Start date Start date Jul 17, 2005

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Jul 17, 2005
#1
  • Jul 17, 2005
  • #1
I am due for an oil change here and i am wondering if i should sap over?
My motor has 133k on it.
 
B

bjgt2

Founding Member
Jul 29, 2001
60
0
0
ny
Jul 17, 2005
#2
  • Jul 17, 2005
  • #2
my car has been using synthetic since it had 25000 miles on it, which is a little late for a car. at over 100k on the car all the synthetic will do is clean out the groves and make the engine lose compression. that is what i have heard anyway. feel free to correct me if I am wrong
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Jul 17, 2005
#3
  • Jul 17, 2005
  • #3
If you have made it to 133K on regular oil I would just stick with what is working.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Jul 17, 2005
#4
  • Jul 17, 2005
  • #4
With that many miles, keep using regular oil. IMO at that level, the "damage" is already done.

My new motor has about 70 miles on it, i'll be switching to synthetic at about 500 miles
 

Curse

Member
Apr 8, 2004
791
2
16
El Paso, TX
Jul 17, 2005
#5
  • Jul 17, 2005
  • #5
bjgt2 said:
my car has been using synthetic since it had 25000 miles on it, which is a little late for a car. at over 100k on the car all the synthetic will do is clean out the groves and make the engine lose compression. that is what i have heard anyway. feel free to correct me if I am wrong
Click to expand...
A lot of people I trust have told me that. Is it the same for evey part of the car(diff, tranny etc.)?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 17, 2005
#6
  • Jul 17, 2005
  • #6
IMHO it comes down to the individual motor (or component, since trannies, etc were mentioned). No real rule of thumb - just some common sense.
Doing something like an Auto Rx and a short OCI on synthetic and then extending the intervals has worked for many many people.

If a motor has had decent oil and decent OCI's, I would take that motor with 150K for a synthetic conversion over a motor with 25K that seldom had the oil changed, and when it was, it was with cheapo (like old G-I) oil.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jul 17, 2005
#7
  • Jul 17, 2005
  • #7
" i am wondering if i should sap over?"

I wouldn't 'sap' it over with that many miles on it - chances are you'll find some leaks if you do.
 

Curse

Member
Apr 8, 2004
791
2
16
El Paso, TX
Jul 18, 2005
#8
  • Jul 18, 2005
  • #8
Very interesting HISSIN50 & Michael, I too have been pondering swapping to synthetics for awhile. With this new information, not sure I want to take that risk. Thanks guys.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Jul 18, 2005
#9
  • Jul 18, 2005
  • #9
IN my experience, manual tranny's and diffs are just as prone to the potential leak issues that show up when high mileage engines are switched. My tranny is relatively new - switch to Amsoil synth atf worked fine. My rear end came out of a turbo wagon with over 200K on it -- I had to pull the rear cover off and go back with a new gasket/sealer/bolts to stop it from leaking when I switched to Amsoil synth diff lube. Same issue on at least 2 other cars that had higher miles on the rear end when switched.
 

sunil6784

Member
Mar 31, 2005
620
0
18
Boston, MA
Jul 18, 2005
#10
  • Jul 18, 2005
  • #10
I just changed mine motor oil over to synthetic. I LOVE it. Definitley a big difference. Makes me feel better that I know my motor is getting the best lube. BTW, my car has 69,000 miles on it.

Next up will be tranny fluid and diff fluid
 

olymaster

New Member
May 15, 2005
179
1
0
columbus ga
Jul 18, 2005
#11
  • Jul 18, 2005
  • #11
i waitng till i get 3000 miles on my new engine before synthetic
as per the engine manufacturer
synthetic should not be used during breakin unless it comes with it from manufacturer like a viper or whatever
 

sgarlic

Founding Member
Apr 21, 2001
3,085
1
56
Jul 18, 2005
#12
  • Jul 18, 2005
  • #12
Foxfan88 said:
I am due for an oil change here and i am wondering if i should sap over?
My motor has 133k on it.
Click to expand...

Absolutely. Better late than never. If you develop a leak, just replace the gasket.
 

TrophyHead

15 Year Member
Mar 18, 2003
1,195
11
49
PA
Jul 18, 2005
#13
  • Jul 18, 2005
  • #13
What do you guys think about Syntech. It's like half and half of regular oil and synthetic. It's working good for me no mysterious oil leaks.
 
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