Blinking overdrive light... again

[3day240sx]

I have seen many "my OD light on my shifter is blinking" but I haven't seen one that was in a 90 or 91 that the light is on the dash. Will the pre 92 blink down on the dash and shift hard or do they just fart and stop pulling in OD?

Thanks

 

[yotee]

i'm thinking if your trannie is an e40d then it is the same. i could be wrong.

 

[3day240sx]

I'm asking because I am going to look at a 90 f350 CC lwb srw that supposedly needs a trans flush.

 

[GenLightening]

The '90 has a switch and light on the dash to take it in and out of OD. The later ones have it on the shifter (not sure the exact year).

 

[3day240sx]

But do both of them blink when the trans goes in limp mode?

 

[GenLightening]

Yes.

 

[3day240sx]

Thank you. When I go look at it I will keep that in mind.

 

[sootman73]

do not flush an auto trans. especially if you dont know its entire service history. drop the pan, clean it, replace filter, put new RUBBER gasket on. flushing can potentially burn the trans up in under two weeks. the new detergent in the new fluid will pick up whatever is in the pan and send up through the trans and clutches. not worth the risk to save a little time...... plus the cost difference is minimal.

 

[trackspeeder]

The '90 has a switch and light on the dash to take it in and out of OD. The later ones have it on the shifter (not sure the exact year).

92 model year moved the OD switch to the column.

 

[3day240sx]

I knew about not flushing a trans if it had more then 30k miles on it without a flush but never knew the exact reasoning so thank you for the details. This has been a lot of help. Thanks every one.

 

[Captain]

Thought I would chime in here.

Regarding trans flushing. I have seen where the only way to successfully flush a 7.3 or any one for that matter is to first do a complete pan and fluid change making sure everything on the bottom end is clean.

Then some transmission shops have a portable outside fluid pump and filter machine that continuously circulates and filters the new fluid change over and over again until the fluid flow is checked for complete cleanliness.

So with this capability flushing should be a big plus. If anyone reasons otherwise I would like to know their basis for that opinion.

Thanks

Captain Dave