Landracing Forum
Bonneville Salt Flats Discussion => Bonneville General Chat => Topic started by: ronnieroadster on May 28, 2015, 04:54:25 PM
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The crew was sitting around thinking about things and this question came up.
Would flat towing a race car for so many miles at speed week with an automatic transmission cause a problem with the transmission? I'm thinking the average tow to the line and then returning to the pits after a run could be as much as 18 to 20 miles the transmission in question is a Ford C-4.
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Ron,
Here is a link that Rob discussed a problem flat towing the 3838 Vinson/Allison Corvette at Bonneville.....Post #60:
http://www.landracing.com/forum/index.php/topic,11552.60.html
Looks like you probably should do the trailer thing as several suggested.
Gregg
PS
See you next week in Wilmington?
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Ronnie, I have fried tailshaft bushings in my short tailshaft C-4. At Bonneville it's trailer time now. Another reason I want to qualify for the long course. :wink: :cheers: Wayno
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Just run the long course :-)
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We used to have that problem with our roadster with a turbo 400. We finally drilled the tailshaft bushing and installed a grease fitting, one squirt a day did the trick.
You could also convert to floating axles, that's how we handle that now that we run a Jeffco transmisson.
Have fun Eric
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It will also be spinning the low/reverse planetary with the rear shaft & bushings, not a good idea. Even more of an issue if you click the engine at speed after a run, an electric lube pump will save your a$$.
Sid.
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Thanks for info guys loading the car on a trailer after a run is not impossible thankfully I have a tilting deck trailer but we hadn't planed on towing that way. I talked to a transmission guy this evening about using an electric pump in line with the cooler he felt that would solve the problem.
Eric I like the idea of a grease fitting on the tail housing bushing that's an easy upgrade.
Wayno I appreciate your input my C-4 has been shortened 7 inches adding the grease should help. Ill keep my fingers crossed you qualify for the long coarse to shorten the ride.
Sid more good info the lube pump no matter what should help.
Gregg yes we will see you next weekend we have a couple of things we need to sort out before the long tow to the salt.
Ron
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You will definitely want to address this problem! It cost us a record.😭 I like the idea of an electric pump plumbed from the pressure testing port from the pan. It's a bit easier than dealing with putting a low car on a trailer.
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Saving scuffing the tires on a long tow back will
save you $$$$$
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The fellow who builds my transmission explained to me the correct way to hook up a pump to circulate the fluid when flat toeing the car. First you need to add a new line from the pan which you then hook up to one side of the pump the other side of the pump returns to the rear oil line cooler fitting on the side of the case. You need to add a shut off valve to the forward line while using the pump. Its really simple to do if you want to flat toe at least a C-4 ford transmission. :cheers:
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Not sure if was the runs or the towing but I had a lot of trouble with tailshaft housing bearings in my Richmond 5 speed. Uses a TH400 bearing and yoke. Basically as I see it there is no lube getting there normally anyway, no surprise it cooked. Perhaps in an auto but I know they have trouble too, thus roller bearing tailshaft housings for them and powerglides. I couldn't make the normal bearing last so I machined the tail housing (by the way, G force trans which seems to be a copy of the Richmond in some respects as well as a Jerico has or can be had with roller bearing tailshaft) to take a roller bearing and then put a little plastic Chinese oil pump with lines from the drain plug to the tail housing with switch that I turn on (gotta remember :) ) when towing or running. So far so good. the stock was definitely not happy with 9500+rpms.
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My trans guy says... oh hang on that's me! :-D
What I have is one of these pumping from the pan through a -6 Hilborn valve with a lite spring to the line pressure port on the back of the trans. The one way valve prevents line pressure loss through the 12v pump while the engine is running & then the remote pump is activated with a relay when the engine is clicked & directly feeds the the back of the trans where it's needed. This will also supply enough lube for coast down after a run with engine off.
Sid.
http://www.ebay.com/itm/251584468221?_trksid=p2060353.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT
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Sid, this will probably be a good fix.
We noticed that not only did the tail shaft bushing burn up all clutch plates and bearing in the rear also burned up. For this reason, I believe a grease fitting for the tail shaft bushing to be an inadequate fix.
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But it's a good fix in a 4-speed stick if you take reverse out.
A little off subject, but a word to the wise.
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Rob, you might want to take a good look at the low/reverse planetary bearings with all that going on, what trans do you run?
I actually have seven of these pumps in my liner oiling both diff's, both O/D's, both transfer cases & the trans.
Sid.
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With small pneumatic tires instead of the casters
http://ecx.images-amazon.com/images/I/41KT9J2O5wL._SY300_.jpg