Push starting an automatic THM125C? Anybody tried? (Page 1/2)
cebix NOV 22, 04:06 PM
Anybody tried this with success? I'm wondering what is possible with an emergency situation, like a dead battery or starter. Thanks.
Patrick NOV 22, 04:14 PM

I don't believe it's possible to push-start a vehicle with any type automatic transmission.
cebix NOV 22, 04:27 PM
I believe there is since there is a way of doing that in an old Mercedes owners manual. Not much a push start but a tow start is possible at about 20 30 mph.

That's why I decided to post this topic to see if it's possible with GM stuff too.

EDIT: Here's an exempt from that manual. It's from a diesel but I don't think that makes a difference except for the preglow instructions.

[This message has been edited by cebix (edited 11-22-2020).]

Raydar NOV 22, 06:10 PM
I still remember the late 50s and early 60s cars that we had when I was a kid. Those were able to be push started. But I think that changed with most of the modern stuff. I think the pump has to be running for anything to engage.
eti engineer NOV 22, 07:37 PM
You cannot push start nearly any automatic made since 1970 or even a bit earlier.
theogre NOV 22, 07:42 PM
Not happening to GM Ford and many other AT vehicles.

Further Towing w/ drive wheel on ground will wreck most AT vehicles fast.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

MarkS NOV 22, 08:52 PM
For an automatic transmission to allow push starting, it needs to have a 2nd pump driven by the driveshaft. The older Chevy Powerglides had that but eventually even those lost the rear pump.

[This message has been edited by MarkS (edited 11-22-2020).]

Dennis LaGrua NOV 23, 09:24 AM
As stated here, push starting any car with an automatic transmission is not possible. Today modern technology has brought us booster packs that are only slightly bigger than a cell phone. Should you need a boost its a good idea to carry one of these with you . I've used them and they work great. You can find them on amazon.com .

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

cvxjet NOV 23, 11:56 AM
I remember a joke about starting an Automatic trans car from when I was young......

About five years ago the battery in my beat-up VW Beetle had died because I left the lights on overnight.

I was in a hurry to get to work on time so I ran into the house to get my wife to give me a hand to start the car.

I told her to get into our second car and use it to push my car fast enough to start it. I told her that because the VW had an automatic transmission, it needed to be pushed at least 30 mph for it to start. She said fine, hoped into her car and drove off.

I sat there growing steadily more angry, wondering where she was and what she could be doing. A minute later I found out when I saw her in the rear-view mirror coming at me at about 40 mph—and I realized that I should have been a bit clearer with my directions.
cebix NOV 23, 12:12 PM
Thanks for all your replies. That solves it then.

I guess Mercedes still had this old system in their transmissions. The exempt I posted is from a 1991 190D.