Rough shifting Transmission advice 4r100

lashidalgo · 01-05-2021, 06:15 PM

Hi There, my van a 2002 E-350 v8 EB is shifting rough between the 3-4 up and down.
I bought it with 140k miles and now I'm at 190k. I have no idea if it was serviced before I purchased it, I also have no idea about automatic transmissions since I've been driving stick my entire life. When I bought it shifted smooth.

When going uphill the van downshifts from 4th -> 2nd (skipping 3rd) and it feels fine. Then it shifts 2nd->3rd and it feels like a punch, you can hear it !. It remains in 3rd for a short amount of time before going back to 4th at super low revs, then it loops back to 2nd trying to hunt the right gear between 2nd-4th like if the 3rd slipped through. While this hasn't been an issue to get around, I noticed the punch is getting worst. I also feel the punch every time I accelerate in flat going from 3rd to 4th.
When engaging reverse, after shifting the stick it takes like 0.5 to a second to engage, if I give it gas at that time the same punch comes back.

I have no idea where to start first, should I try to send it for a full flush, change the oil? or straight up just rebuild it?

I know is a hard question to answer without physically looking at it. I'm seeking some advice on whats the best way to proceed since I've read horror stories about transmission flushes and I'd like to avoid a rebuild if possible.

If you also know a reputable transmission shop in WA Id to be very happy to get it there and have them take a look at it.

Salute!

REF · 01-05-2021, 10:39 PM

The 4R100’s tend to have a life span, and often have issues around that mileage. Could be torque converter. Check your fluid to see if it smells burnt. If so, your clutches might be fried, have you run high trans temps lately? It could also be in the valve body. Check in with John Wood

http://jwtt.com/home

JWA · 01-06-2021, 07:09 AM

Quote:

Originally Posted by lashidalgo

I know is a hard question to answer without physically looking at it. I'm seeking some advice on whats the best way to proceed since I've read horror stories about transmission flushes and I'd like to avoid a rebuild if possible.

What horror stories have you heard about transmission flushes?

If your concern would be a full fluid exchange or "flush" causes problems that's 100% wrong IF they're done properly--and that's easily accomplished. IF your transmission already has issues a flush won't do anything to create more problems.

I've done it DIY on a 4R70-W with over 250K miles, approaching 292K miles on that same transmission today.

To better assess what needs to be done take your van to a local trusted transmission shop and have them diagnose any "codes" or DTC's you may have.

carringb · 01-06-2021, 07:30 AM

1) It's probably toast. The harsh shift is a strategy to extend the life of the transmission when it detects excess slip or excess temps.

2) I'd go ahead and do a full flush anyways. By this, I mean a full drain and fill aka "the bucket method", or a fluid exchange machine that uses the transmission's own pump. The pressurized machines used by quick-lube centers can cause damage. Dealers and reputable transmissions shops don't use them. When the flush is done, an inline filter should be added. The reason I say go ahead and try it... some symptoms including slip are made worse by contaminated fluid. And if you have the original fluid, this could be causing all the issues on its own. And most important, you'll start removing debris from the system. Any debris remaining in the system, especially the coolers, can damage the rebuild.

3) The harsh shift when you shift to reverse using throttle is normal, but don't do that. Old fluid can extend shift times, but when you give it throttle, you're basically doing a neutral-drop. Your transmission doesn't like this.

Where in Washington are you?

BTW - if you DIY the fluid flush, make sure the new fluid meets MERCON-V spec. Dec/Merc does not. Dex-V is only 1-2 dollars more per quart. The Napa stuff is good. The fancy multi-grade stuff is fine too (like Valvoline Max Life) but usually costs more.

JWA · 01-06-2021, 09:06 AM

Quote:

Originally Posted by carringb

2) I'd go ahead and do a full flush anyways. By this, I mean a full drain and fill aka "the bucket method", or a fluid exchange machine that uses the transmission's own pump. The pressurized machines used by quick-lube centers can cause damage. Dealers and reputable transmissions shops don't use them. When this is done, an inline filter should be added. The reason I say go ahead and try it... some symptoms including slip are made worse by contaminated fluid. And if you have the original fluid, this could be causing all the issues on its own. And most important, you'll start removing debris from the system. Any debris remaining in the system, especially the coolers, can damage the rebuild.

Great advice---I think most rebuilt transmissions and/or local rebuilders specify the end user or installing mechanic install an in-line filter to keep the warranty intact. Plus its just a good idea too.

It's also highly recommended to use the aerosol cans of transmission flush for the lines as well as the existing coolers and lines---also another good idea.

BTW - if you DIY the fluid flush, make sure the new fluid meets MERCON-V spec. Dec/Merc does not. Dex-V is only 1-2 dollars more per quart. The Napa stuff is good. The fancy multi-grade stuff is fine too (like Valvoline Max Life) but usually costs more.[/QUOTE]

Here's a DIY link I've always found useful: https://www.ford-trucks.com/articles...-transmission/ Having done this single-handed its far easier than one might think.

Plus I discovered buying ATF from my local Ford dealership was cheaper than the good stuff from NAPA etc. Do keep in mind you'll use upwards of 18 quarts when this job is complete. Keep the receipt as it might be helpful should any questions arise during a warranty claim.

lashidalgo · 01-07-2021, 01:25 PM

Quote:

Originally Posted by carringb

Where in Washington are you?

Issaquah!, near Bellavue.

Thank you, everyone, for the replies after checking the link for the procedure I realized I had no idea about anything in there. I'll start by finding a good transmission shop and having them take a look, hopefully, a fluid change will do the trick.

twotimer · 01-12-2021, 08:12 AM

I have the same transmission in a 2003 E-350 Quigley 7.3PSD. At 120K I decided to have my transmission bulletproofed. I don't regret it. If you plan on keeping the van long term, I think it is worth the "investment". I used a company out of Georgia that specializes in the 4R100. https://www.a1transga.com