I took my truck to a tranny garage because I felt it sleeping every now and than. (Rarely but definitely slipping). He said I have a sliding 1-2 and a lazy 3-4. Said he would rebuild it for $1500 and if I wanted he can make it shift harder or softer. Any suggestions with that and what do you guys think about the diagnostics he came up with? My seal on the rear diff that connects to my driveshaft is also leaking a little bit so I'm going to have him replace that as well for another $150 because he is also going to fix the pitch on the differential because I guess when I put my lift in, I didn't change the angle of it and now my U joints are going. What do you guys think of all this? Any similiar problems? Thanks in advance.

 

How many miles on it, and have you ever changed the tranny fluid?

 

About 102,000 miles on it right now and has never been beat on because it used to be my grandpas truck and I'm 95% sure the tranny fluid has never been changed. And I'll go with the stage 2. He said he won't flush it because it will just speed up the process of it ****tin the bed and it is too much of a liability.

 

I would sure rather spend the $150 for a fluid EXCHANGE (not a flush) and get a good chance of fixing the issue instead of spending $1500 for a rebuild. 100k on tranny fluid is NOT really excessive. Worst case, you will have to rebuild anyway.

He's just trying to sell you a rebuild, take it elsewhere for the fluid exchange.

 

Not necessarily the filter - the tranny filter in these things is a rather coarse screen. It's gonna be more than $150, but some shops will drop the pan, replace the filter, AND do a fluid exchange with a machine.

 

So you guys suggest changing the fluid without a flush and what about the pitch on my differential and driveshaft? I'm assuming that should be fixed as well and a new seal put in.

 

You need a machine for a complete fluid exchange - the pan only holds 5 quarts or so and the total capacity is around 14 quarts. You just want the machine to be used in the PASSIVE mode - with the engine running and the tranny pump doing the work of pumping the old fluid out and sucking the new fluid in. Do *NOT* use flush chemicals.

 

He said if I don't change the pinion and differential angle. My seals are just going to keep going and going and my u joints are will keep going as well. My dad seemed to think the same way but I never read anywhere when researching about my lift of anyone else doing this or having that problem.

 

I lifted mine with spindles, a coil spacer and in the rear add a leaf and blocks so it wasn't necessarily a "kit". So it wouldn't come with anything to change the pinion angle if needed. Should I find specs on a stock f150 than adjust the angle to stock?

 

Do the rebuild. He will probably throw in some sort of warranty. I did a stage 2 on my truck and included an upgraded stall converter and red band Kevlar clutches. Totally worth the investment. A quick and crisp shifting transmission makes all the driving difference in the world. If you are looking to save some $$$ go with the flush but make sure it is done as GLC describes it. It may resolve your 1-2 issues but probably not. 1-2 seems to be the first to go on the 4r70 that the 4.6 is mated to. It is also a pretty simple fix if you have tools and good hands.