jerry007

Please give me some wise advice on this one. My 2003 48re is not going into High gear or overdrive. It has 90,000 mile , never really towed that much and it has been serviced regularly. Need some expert advise on what to do without being ripped off. Thanks for any replies.

cdennyb

Jerry, STOP... dont buy anything expensive just yet. Mine did the same thing at 80K miles and after considerable expense and headache I finally traced it to the connector on the firewall that connect the ECM, PCM,and transmission. Disconnect the batts, get a can of contact cleaner and go to work on all three. I found it took a couple of cleanings to get it solved. I now have 165K on the ol girl and havent had an issue since I cleaned them. Theres a tech bulletin out there somewhere about this problem and i'll look for it. PM with your address and I'll email it to you.

cody459

Like the previous post stated sounds like an electrical issue, mine did the same thing when I drove through a big puddle of water and knocked of the ground on the passenger side battery. I've been through 3 tranny's and even when they were at there worse they would eventually shift into OD, might haven taken awhile but they still shifted up.

jerry007

thanks a lot guys. definitly sounds like electrical issue. thank you again . e-mail jerry007@bellsouth.net. God bless!

cdennyb

Jerry: Already sent this to you via your email because I figured you needed soooner than later but for everyone else who might have a similiar problem... here it is.

jerry007

Thanks so much cdennyb, I just got through cleaning al three connecters on the firewall (ECM). It shifts PERFECTLY now. Man I cannot thank you enough!!!! God bless.

KRN

This post saved me a lot of time and money, i've got about 75K relatively easy miles on my truck and all of a sudden it stopped shifting into 4th and overdrive. The PCM plugs looked fine, but I cleaned them with contact cleaner anyway, and then dried them out, put some contact gel on them, plugged them in, hooked the batteries back up and that was it ... started shifting properly again ... what a great feeling. Thanks.

Lost Lake

Wow. This kind of information can save a guy's sanity and pocketbook.

My wife is upset I spend so much time on these forums, but the knowledge that is here is priceless.

Thanks to everyone who figures this stuff out and then posts it for all of us to benefit!!!

VictorC

Just another thanks for posting this, very valuable info.