Getting back om the road after a blown radiator

Bought my new to me 1987 4.0 Comanche. Pulled it into the garage after buying it and it pukes. Pulled it apart to discover that one of the plastic end tanks had split open. Looks like the previous owner had converted to the later open style system so I made sure to get a later model radiator. Got it in, apparently there's no provision for the aux fan temp sensor. No biggie since the previous owner bypassed it to a switch on the dash anyway.

So here's The issue. Coolant came out of the transmission cooler lines. I'm going to try and change the fluid but I've read you only really get half of the aw4 fluid from dropping the pan. I'm Just trying to figure out how to get back running without trashing a transmission that feels like it's nearing the end of it's life anyway. (Shifts don't feel great, doesn't move in first with my foot off the brake etc )

Thanks for any help!

Green_Manche said:

So here's The issue. Coolant came out of the transmission cooler lines. I'm going to try and change the fluid but I've read you only really get half of the aw4 fluid from dropping the pan. I'm Just trying to figure out how to get back running without trashing a transmission that feels like it's nearing the end of it's life anyway.

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You need to get all the coolant out of the trans immediately.
Pull the transmission pan, change the filter, reinstall, fill and then do a total flush by removing the cooler return line.
With the engine idling, drain the fluid out of the return line 3-quarts at a time, shut the engine off and add 3-qt fluid.
Repeat and keep flushing until the fluid changes from the old to the new oil color.

lazyxj said:

You need to get all the coolant out of the trans immediately.
Pull the transmission pan, change the filter, reinstall, fill and then do a total flush by removing the cooler return line.
With the engine idling, drain the fluid out of the return line 3-quarts at a time, shut the engine off and add 3-qt fluid.
Repeat and keep flushing until the fluid changes from the old to the new oil color.

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I know it's late but I wanted to say thanks for your help. Took about 3.5-4 gallons to get it to come out nice and red but it eventually did. Now I get to figure out some of the other issues this thing has. I've been driving it some and really liking it except it still gets warm too easily and the steering is driving me nuts but it'll get there lol.

It is normal for these to run at 210. If you have an IR gauge to verify your temp, your stock gauge may be read incorrectly.
For steering, you probably need to replace most of it. Trackbar, draglink, and I recommend either a V8 ZJ tie rod or aftermarket. Definitely check your control arm bushings as well.

Johnnie Walker said:

It is normal for these to run at 210. If you have an IR gauge to verify your temp, your stock gauge may be read incorrectly.
For steering, you probably need to replace most of it. Trackbar, draglink, and I recommend either a V8 ZJ tie rod or aftermarket. Definitely check your control arm bushings as well.

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I'm pretty sure it's got a lower tstat in it though. Im not 100% sure because the only thing Ive done to the jeep is replace the radiator and change the door locks. It stays a very constant 190 driving down the road and climbs up during parking lot usage. Nothing under the front end is factory. It's got a homemade 4 link with a waggy 44 and somewhere around 8ish inches of lift. I believe the bushings just got changed (PO gave me a reciept) but I need to verify that as well as all the ball joints. I just need to figure out the best way to check all that. I'd rather not rip it all apart if not mandatory. I'm going to try and get some pictures on photobucket so you all can see some of this...homebrewing.

Getting hot at low speeds is usually an airflow problem. It might be worth replacing the fan clutch. They are a wear item and usually wear out after 5-6 years.

I'll have to look into that Thanks. I got a new symptom last night. It would spit coolant out past the radiator cap (no overflow bottle at the moment) so I'm wondering if the cap is shot. It never got over 210 last night according to the gauge so I'm going to try and have the cap tested and see if I get anywhere with that. Also learned after getting a headache I have an exhaust leak somewhere I need to trace down -.-

Got a new cap. It looks and feels exactly like the old one. The radiator filler neck doesn't seem damaged or bent in Anyway but when I pulled the cap off the coolant was already dirty after about an hour of run time on it so I'm wondering if it needs a professional flush.