TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC V8 Engine Repair and Modifications
  New Posts New Posts RSS Feed - Gremlin X 343 Oil
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

Gremlin X 343 Oil

 Post Reply Post Reply Page  12>
Author
Message
betanu961 View Drop Down
AMC Fan
AMC Fan
Avatar

Joined: Oct/24/2017
Location: Asheville, NC
Status: Offline
Points: 8
Post Options Post Options   Thanks (0) Thanks(0)   Quote betanu961 Quote  Post ReplyReply Direct Link To This Post Topic: Gremlin X 343 Oil
    Posted: Feb/18/2018 at 10:08am
I searched but couldn't find any information on this.

I have a 1974 Gremlin X with a 343 V8.  I generally use 10w30 conventional oil.  Anyway, when I took it in for regular service they changed the oil out and put 75w90 synthetic in its place (not sure why).  Will this cause any issues?


Edited by betanu961 - Feb/18/2018 at 12:54pm
Back to Top
73hornut View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/03/2007
Location: Southern Oregon
Status: Offline
Points: 3132
Post Options Post Options   Thanks (0) Thanks(0)   Quote 73hornut Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 10:56am
Originally posted by betanu961 betanu961 wrote:

I searched but couldn't find any information on this.

I have a 1974 Gremlin X with a 343 V8.  I generally use 10w30 conventional oil.  Anyway, when I took it in for regular service they changed the oil out and put 75w30 synthetic in its place (not sure why).  Will this cause any issues?
Probably 5w30, never heard of 75w30?
71 Javelin
74 Gremlin
79 Spirit AMX
Rogue Valley Rumblers
Like Us on FB
https://www.facebook.com/groups/1602825606650796
Back to Top
amxdreamer View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/30/2008
Location: Vancouver, BC
Status: Offline
Points: 8494
Post Options Post Options   Thanks (0) Thanks(0)   Quote amxdreamer Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 11:29am
or maybe 15w30...either way it will be fine.
Tony
Vancouver, BC
1970 AMX
1972 Badassador
AMO#10333
Back to Top
401MATCOUPE View Drop Down
AMC Addicted
AMC Addicted


Joined: May/20/2010
Location: Salisbury, MD
Status: Offline
Points: 5370
Post Options Post Options   Thanks (0) Thanks(0)   Quote 401MATCOUPE Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 12:13pm
Depending on the health of the engine, you might start seeing oil leaks with synthetic oil after a life time of Conventional Oil.  If that 343 had a lot of miles, I have seen some engines start to use oil too....proceed with caution.
Ross K. Peterson
68X,GoPac,343,AT,52A(1stCar)
68X,GoPac,390,4sp,52A
69X,GoPac,390,4sp,64A
70X,GoPac,390,4sp,87A,8
70X,GoPac,390,4sp,BBO,8
70 Jav SST,390,AT,BSO
74MatX,401,AT,Prototype
74MatX,401,AT
Back to Top
betanu961 View Drop Down
AMC Fan
AMC Fan
Avatar

Joined: Oct/24/2017
Location: Asheville, NC
Status: Offline
Points: 8
Post Options Post Options   Thanks (0) Thanks(0)   Quote betanu961 Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 12:51pm
Not entirely sure how many miles were on the engine before it was installed into the Gremlin.  It came from a Javelin.

Do you think it would be prudent to drain the synthetic and put in 10w30 again?
Back to Top
betanu961 View Drop Down
AMC Fan
AMC Fan
Avatar

Joined: Oct/24/2017
Location: Asheville, NC
Status: Offline
Points: 8
Post Options Post Options   Thanks (0) Thanks(0)   Quote betanu961 Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 12:55pm
Originally posted by 73hornut 73hornut wrote:

Probably 5w30, never heard of 75w30?

Sorry, it was 75w90.
Back to Top
jav343 View Drop Down
AMC Nut
AMC Nut
Avatar

Joined: Sep/26/2011
Location: CO
Status: Offline
Points: 293
Post Options Post Options   Thanks (0) Thanks(0)   Quote jav343 Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 1:18pm
Originally posted by betanu961 betanu961 wrote:

Originally posted by 73hornut 73hornut wrote:

Probably 5w30, never heard of 75w30?

Sorry, it was 75w90.


75W90 is gear oil...
2000 Dodge Durango SLT 4.7L, 1997 Jeep Wrangler 4.0L, 1968 AMC Javelin 5.6L 
Back to Top
tyrodtom View Drop Down
AMC Addicted
AMC Addicted


Joined: Sep/14/2007
Location: Virginia
Status: Offline
Points: 6199
Post Options Post Options   Thanks (0) Thanks(0)   Quote tyrodtom Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 1:23pm
There isn't a 75w90 engine oil either.
The thickest synthetic I've heard of is 15w50,   though some specialty makers may make something a little thicker,  but nobody even approaches 75w90 territory for engine oils.
75w90 is in the weights that gear oils commonly come in ,   no even semi-experienced mechanic would put that in a engine.

I think you heard them wrong. Or did they change your rear end oil too?
  First, you need to find out what they really put in your engine. 


Edited by tyrodtom - Feb/18/2018 at 2:16pm
66 American SW, 66 American 2dr, 82 J10, 70 Hornet, Pound, Va.
Back to Top
amc67rogue View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Nov/05/2008
Location: Phx. AZ.
Status: Offline
Points: 1578
Post Options Post Options   Thanks (0) Thanks(0)   Quote amc67rogue Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2018 at 2:44pm
Sniff the oil on the dipstick ,Gear oil usually has a sulpher oder to it.
Keith Coggins 67Rogue X code
Back to Top
Lyle View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/17/2014
Location: None
Status: Offline
Points: 772
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lyle Quote  Post ReplyReply Direct Link To This Post Posted: Feb/19/2018 at 10:59am
Take it back and have them change the oil again (for free) if the receipt states 75W90 or have a different shop change the oil.
Gear oil should not be in an engine and I wouldn't gamble on an engine for the sake of an oil change.
Back to Top
 Post Reply Post Reply Page  12>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.141 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or