Tq converter problem?

[AdamDude04]

89 Bronco XLT 5.0 backed by a E40D

Truck shifts smooth as a babies but driving around in town.. but in town for them 45-55mph speed limits surrounded by 35-45mph roads.. sometimes I just drop it into OD so for those high speed side streets, I can keep the RPMs low.

However..the first few gears are smooth shift when accelerating. But once it goes into OD, it clunks bad. Still drives, no loss in power but it does clunk.

It also shutters if giving it gas and the RPMs in OD are just under 1k. However OD loves when the RPMs are 1300 or more.

And another issue is when slowing down.. it also likes to clunk between 35-20mph..I assume at those speeds it's 3rd into 2nd?

This is most the time, however there are those days when everything shifts smooth and no issues at all.

ideas? I got a 390hp/420tq motor to be installed sometime this summer so I asusme I'll need a tranny rebuild as well..or maybe an upgrade of internals to handle the added power?

 

[miesk5]

yo;

First, have you pulled Diagnostic Trouble Codes? If not, do it and report Codes if any;

a Self Test by my pal, BroncoJoe19

do the KOEO = Key On Engine Off portion first

& Remember to have engine @ Normal Operating Temperature before doing the KEY ON ENGINE RUNNING (KOER) portion

Turn off all lights, radio, etc.

You wrote; "...sometimes I just drop it into OD..." How do you do that?

By using da OD Switch on the dash? If so, that is just for turning OD OFF so it Won't shift into OD; or leaving OD available for the tranny to shift from 3rd into OD in a steady cruise condition.

check fluid condition; should be redish not bronwbish or have wtaer whitish deposits on dip stick and not have burnt toast aroma.

I doubt the tranny will handle that engine upgrade as is.

See this; http://offroad.automotive.com/125174/1001or-ford-bronco-e40d-transmission-rebuild/index.html

and http://www.transmissioncenter.net/e4od.htm

Be aware that most offer drag rebuilds or new units with High Stall TCs; so ensure that any rebuild is specifically written-up before having any work done.

 

[AdamDude04]

Unfortantly no codes in either mode. Truck has been doing this the last year.. and some days it's smooth and some days it's rough.

I'm about to check the tranny fluid today..but last time I checked it 6 months ago, itw as fine..